Add support for loop breaks and function returns
This commit is contained in:
parent
c6b3155d52
commit
fbb5b72f24
207
src/engine.rs
207
src/engine.rs
@ -11,24 +11,28 @@ use std::ops::{Add, Sub, Mul, Div};
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use std::cmp::{Ord, Eq};
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#[derive(Debug)]
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pub enum EvalError {
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FunctionNotFound,
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FunctionArgMismatch,
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FunctionCallNotSupported,
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IfGuardMismatch,
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VariableNotFound,
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FunctionArityNotSupported
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pub enum EvalAltResult {
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ErrorFunctionNotFound,
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ErrorFunctionArgMismatch,
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ErrorFunctionCallNotSupported,
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ErrorIfGuardMismatch,
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ErrorVariableNotFound,
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ErrorFunctionArityNotSupported,
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LoopBreak,
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Return(Box<Any>)
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}
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impl Error for EvalError {
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impl Error for EvalAltResult {
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fn description(&self) -> &str {
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match *self {
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EvalError::FunctionNotFound => "Function not found",
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EvalError::FunctionArgMismatch => "Function argument types do not match",
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EvalError::FunctionCallNotSupported => "Function call with > 2 argument not supported",
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EvalError::IfGuardMismatch => "If guards expect boolean expression",
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EvalError::VariableNotFound => "Variable not found",
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EvalError::FunctionArityNotSupported => "Functions of more than 3 parameters are not yet supported"
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EvalAltResult::ErrorFunctionNotFound => "Function not found",
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EvalAltResult::ErrorFunctionArgMismatch => "Function argument types do not match",
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EvalAltResult::ErrorFunctionCallNotSupported => "Function call with > 2 argument not supported",
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EvalAltResult::ErrorIfGuardMismatch => "If guards expect boolean expression",
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EvalAltResult::ErrorVariableNotFound => "Variable not found",
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EvalAltResult::ErrorFunctionArityNotSupported => "Functions of more than 3 parameters are not yet supported",
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EvalAltResult::LoopBreak => "Loop broken before completion (not an error)",
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EvalAltResult::Return(_) => "Function returned value (not an error)"
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}
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}
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@ -37,20 +41,20 @@ impl Error for EvalError {
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}
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}
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impl fmt::Display for EvalError {
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impl fmt::Display for EvalAltResult {
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fn fmt(&self, f: &mut fmt::Formatter) -> fmt::Result {
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write!(f, "{}", self.description())
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}
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}
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pub enum FnType {
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ExternalFn0(Box<Fn()->Result<Box<Any>, EvalError>>),
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ExternalFn1(Box<Fn(&mut Box<Any>)->Result<Box<Any>, EvalError>>),
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ExternalFn2(Box<Fn(&mut Box<Any>, &mut Box<Any>)->Result<Box<Any>, EvalError>>),
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ExternalFn3(Box<Fn(&mut Box<Any>, &mut Box<Any>, &mut Box<Any>)->Result<Box<Any>, EvalError>>),
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ExternalFn4(Box<Fn(&mut Box<Any>, &mut Box<Any>, &mut Box<Any>, &mut Box<Any>)->Result<Box<Any>, EvalError>>),
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ExternalFn5(Box<Fn(&mut Box<Any>, &mut Box<Any>, &mut Box<Any>, &mut Box<Any>, &mut Box<Any>)->Result<Box<Any>, EvalError>>),
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ExternalFn6(Box<Fn(&mut Box<Any>, &mut Box<Any>, &mut Box<Any>, &mut Box<Any>, &mut Box<Any>, &mut Box<Any>)->Result<Box<Any>, EvalError>>),
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ExternalFn0(Box<Fn()->Result<Box<Any>, EvalAltResult>>),
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ExternalFn1(Box<Fn(&mut Box<Any>)->Result<Box<Any>, EvalAltResult>>),
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ExternalFn2(Box<Fn(&mut Box<Any>, &mut Box<Any>)->Result<Box<Any>, EvalAltResult>>),
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ExternalFn3(Box<Fn(&mut Box<Any>, &mut Box<Any>, &mut Box<Any>)->Result<Box<Any>, EvalAltResult>>),
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ExternalFn4(Box<Fn(&mut Box<Any>, &mut Box<Any>, &mut Box<Any>, &mut Box<Any>)->Result<Box<Any>, EvalAltResult>>),
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ExternalFn5(Box<Fn(&mut Box<Any>, &mut Box<Any>, &mut Box<Any>, &mut Box<Any>, &mut Box<Any>)->Result<Box<Any>, EvalAltResult>>),
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ExternalFn6(Box<Fn(&mut Box<Any>, &mut Box<Any>, &mut Box<Any>, &mut Box<Any>, &mut Box<Any>, &mut Box<Any>)->Result<Box<Any>, EvalAltResult>>),
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InternalFn(FnDef)
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}
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@ -63,7 +67,7 @@ pub type Scope = Vec<(String, Box<Any>)>;
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impl Engine {
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fn call_fn(&self, name: &str, arg1: Option<&mut Box<Any>>, arg2: Option<&mut Box<Any>>, arg3: Option<&mut Box<Any>>,
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arg4: Option<&mut Box<Any>>, arg5: Option<&mut Box<Any>>, arg6: Option<&mut Box<Any>>) -> Result<Box<Any>, EvalError> {
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arg4: Option<&mut Box<Any>>, arg5: Option<&mut Box<Any>>, arg6: Option<&mut Box<Any>>) -> Result<Box<Any>, EvalAltResult> {
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match self.fns.get(name) {
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Some(ref vf) => {
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@ -78,6 +82,8 @@ impl Engine {
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}
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}
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& FnType::InternalFn(ref f) => {
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if f.params.len() != 6 { return Err(EvalAltResult::ErrorFunctionArgMismatch); }
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let mut new_scope: Scope = Vec::new();
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let result1 = self.call_fn("clone", Some(a1), None, None, None, None, None);
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let result2 = self.call_fn("clone", Some(a2), None, None, None, None, None);
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@ -95,14 +101,17 @@ impl Engine {
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new_scope.push((f.params[4].clone(), r5));
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new_scope.push((f.params[5].clone(), r6));
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},
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_ => return Err(EvalError::FunctionArgMismatch)
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_ => return Err(EvalAltResult::ErrorFunctionArgMismatch)
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}
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match self.eval_stmt(&mut new_scope, &*f.body) {
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Err(EvalAltResult::Return(x)) => return Ok(x),
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x => return x
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}
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return self.eval_stmt(&mut new_scope, &*f.body);
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}
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_ => ()
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}
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}
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return Err(EvalError::FunctionArgMismatch);
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return Err(EvalAltResult::ErrorFunctionArgMismatch);
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}
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(Some(ref mut a1), Some(ref mut a2), Some(ref mut a3), Some(ref mut a4), Some(ref mut a5), None) => {
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for arr_f in *vf {
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@ -114,6 +123,8 @@ impl Engine {
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}
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}
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& FnType::InternalFn(ref f) => {
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if f.params.len() != 5 { return Err(EvalAltResult::ErrorFunctionArgMismatch); }
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let mut new_scope: Scope = Vec::new();
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let result1 = self.call_fn("clone", Some(a1), None, None, None, None, None);
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let result2 = self.call_fn("clone", Some(a2), None, None, None, None, None);
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@ -129,14 +140,17 @@ impl Engine {
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new_scope.push((f.params[3].clone(), r4));
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new_scope.push((f.params[4].clone(), r5));
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},
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_ => return Err(EvalError::FunctionArgMismatch)
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_ => return Err(EvalAltResult::ErrorFunctionArgMismatch)
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}
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match self.eval_stmt(&mut new_scope, &*f.body) {
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Err(EvalAltResult::Return(x)) => return Ok(x),
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x => return x
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}
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return self.eval_stmt(&mut new_scope, &*f.body);
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}
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_ => ()
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}
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}
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return Err(EvalError::FunctionArgMismatch);
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return Err(EvalAltResult::ErrorFunctionArgMismatch);
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}
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(Some(ref mut a1), Some(ref mut a2), Some(ref mut a3), Some(ref mut a4), None, None) => {
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for arr_f in *vf {
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@ -148,6 +162,8 @@ impl Engine {
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}
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}
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& FnType::InternalFn(ref f) => {
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if f.params.len() != 4 { return Err(EvalAltResult::ErrorFunctionArgMismatch); }
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let mut new_scope: Scope = Vec::new();
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let result1 = self.call_fn("clone", Some(a1), None, None, None, None, None);
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let result2 = self.call_fn("clone", Some(a2), None, None, None, None, None);
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@ -160,14 +176,17 @@ impl Engine {
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new_scope.push((f.params[2].clone(), r3));
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new_scope.push((f.params[3].clone(), r4));
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},
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_ => return Err(EvalError::FunctionArgMismatch)
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_ => return Err(EvalAltResult::ErrorFunctionArgMismatch)
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}
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match self.eval_stmt(&mut new_scope, &*f.body) {
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Err(EvalAltResult::Return(x)) => return Ok(x),
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x => return x
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}
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return self.eval_stmt(&mut new_scope, &*f.body);
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}
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_ => ()
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}
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}
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return Err(EvalError::FunctionArgMismatch);
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return Err(EvalAltResult::ErrorFunctionArgMismatch);
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}
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(Some(ref mut a1), Some(ref mut a2), Some(ref mut a3), None, None, None) => {
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for arr_f in *vf {
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@ -179,6 +198,8 @@ impl Engine {
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}
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}
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& FnType::InternalFn(ref f) => {
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if f.params.len() != 3 { return Err(EvalAltResult::ErrorFunctionArgMismatch); }
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let mut new_scope: Scope = Vec::new();
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let result1 = self.call_fn("clone", Some(a1), None, None, None, None, None);
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let result2 = self.call_fn("clone", Some(a2), None, None, None, None, None);
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@ -189,14 +210,17 @@ impl Engine {
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new_scope.push((f.params[1].clone(), r2));
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new_scope.push((f.params[2].clone(), r3));
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},
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_ => return Err(EvalError::FunctionArgMismatch)
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_ => return Err(EvalAltResult::ErrorFunctionArgMismatch)
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}
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match self.eval_stmt(&mut new_scope, &*f.body) {
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Err(EvalAltResult::Return(x)) => return Ok(x),
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x => return x
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}
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return self.eval_stmt(&mut new_scope, &*f.body);
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}
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_ => ()
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}
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}
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return Err(EvalError::FunctionArgMismatch);
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return Err(EvalAltResult::ErrorFunctionArgMismatch);
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}
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(Some(ref mut a1), Some(ref mut a2), None, None, None, None) => {
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for arr_f in *vf {
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@ -208,6 +232,8 @@ impl Engine {
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}
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}
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& FnType::InternalFn(ref f) => {
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if f.params.len() != 2 { return Err(EvalAltResult::ErrorFunctionArgMismatch); }
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let mut new_scope: Scope = Vec::new();
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let result1 = self.call_fn("clone", Some(a1), None, None, None, None, None);
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let result2 = self.call_fn("clone", Some(a2), None, None, None, None, None);
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@ -216,14 +242,17 @@ impl Engine {
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new_scope.push((f.params[0].clone(), r1));
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new_scope.push((f.params[1].clone(), r2));
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},
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_ => return Err(EvalError::FunctionArgMismatch)
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_ => return Err(EvalAltResult::ErrorFunctionArgMismatch)
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}
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match self.eval_stmt(&mut new_scope, &*f.body) {
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Err(EvalAltResult::Return(x)) => return Ok(x),
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x => return x
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}
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return self.eval_stmt(&mut new_scope, &*f.body);
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}
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_ => ()
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}
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}
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return Err(EvalError::FunctionArgMismatch);
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return Err(EvalAltResult::ErrorFunctionArgMismatch);
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}
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(Some(ref mut a1), None, None, None, None, None) => {
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for arr_f in *vf {
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@ -235,20 +264,25 @@ impl Engine {
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}
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}
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& FnType::InternalFn(ref f) => {
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if f.params.len() != 1 { return Err(EvalAltResult::ErrorFunctionArgMismatch); }
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let mut new_scope: Scope = Vec::new();
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let result1 = self.call_fn("clone", Some(a1), None, None, None, None, None);
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match result1 {
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Ok(r1) => {
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new_scope.push((f.params[0].clone(), r1));
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},
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_ => return Err(EvalError::FunctionArgMismatch)
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_ => return Err(EvalAltResult::ErrorFunctionArgMismatch)
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}
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match self.eval_stmt(&mut new_scope, &*f.body) {
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Err(EvalAltResult::Return(x)) => return Ok(x),
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x => return x
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}
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return self.eval_stmt(&mut new_scope, &*f.body);
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}
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_ => ()
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}
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}
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return Err(EvalError::FunctionArgMismatch);
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return Err(EvalAltResult::ErrorFunctionArgMismatch);
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}
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_ => {
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for arr_f in *vf {
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@ -260,17 +294,22 @@ impl Engine {
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}
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}
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& FnType::InternalFn(ref f) => {
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if f.params.len() != 0 { return Err(EvalAltResult::ErrorFunctionArgMismatch); }
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let mut new_scope: Scope = Vec::new();
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return self.eval_stmt(&mut new_scope, &*f.body);
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match self.eval_stmt(&mut new_scope, &*f.body) {
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Err(EvalAltResult::Return(x)) => return Ok(x),
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x => return x
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}
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}
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_ => ()
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}
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}
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return Err(EvalError::FunctionArgMismatch);
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return Err(EvalAltResult::ErrorFunctionArgMismatch);
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}
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}
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}
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None => Err(EvalError::FunctionNotFound)
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None => Err(EvalAltResult::ErrorFunctionNotFound)
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}
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}
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@ -280,7 +319,7 @@ impl Engine {
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&(clone_helper as fn(T)->T).register(self, "clone");
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}
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fn eval_expr(&self, scope: &mut Scope, expr: &Expr) -> Result<Box<Any>, EvalError> {
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fn eval_expr(&self, scope: &mut Scope, expr: &Expr) -> Result<Box<Any>, EvalAltResult> {
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match *expr {
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Expr::IntConst(i) => Ok(Box::new(i)),
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Expr::StringConst(ref s) => Ok(Box::new(s.clone())),
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@ -290,7 +329,7 @@ impl Engine {
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return self.call_fn("clone", Some(val), None, None, None, None, None);
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}
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}
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Err(EvalError::VariableNotFound)
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Err(EvalAltResult::ErrorVariableNotFound)
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}
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Expr::Assignment(ref id, ref rhs) => {
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match **id {
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@ -304,9 +343,9 @@ impl Engine {
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return Ok(Box::new(()));
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}
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}
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Err(EvalError::VariableNotFound)
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Err(EvalAltResult::ErrorVariableNotFound)
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}
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_ => Err(EvalError::VariableNotFound)
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_ => Err(EvalAltResult::ErrorVariableNotFound)
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}
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}
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Expr::FnCall(ref fn_name, ref args) => {
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@ -361,7 +400,7 @@ impl Engine {
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Some(&mut arg5), Some(&mut arg6))
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}
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else {
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Err(EvalError::FunctionCallNotSupported)
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Err(EvalAltResult::ErrorFunctionCallNotSupported)
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}
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}
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Expr::MethodCall(ref target, ref fn_name, ref args) => {
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@ -371,7 +410,7 @@ impl Engine {
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return self.call_fn(&fn_name, Some(val), None, None, None, None, None);
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}
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}
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Err(EvalError::VariableNotFound)
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Err(EvalAltResult::ErrorVariableNotFound)
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}
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else if args.len() == 1 {
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let mut arg = try!(self.eval_expr(scope, &args[0]));
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@ -381,7 +420,7 @@ impl Engine {
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return self.call_fn(&fn_name, Some(val), Some(&mut arg), None, None, None, None);
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}
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}
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Err(EvalError::VariableNotFound)
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Err(EvalAltResult::ErrorVariableNotFound)
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}
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else if args.len() == 2 {
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let mut arg1 = try!(self.eval_expr(scope, &args[0]));
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@ -392,7 +431,7 @@ impl Engine {
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return self.call_fn(&fn_name, Some(val), Some(&mut arg1), Some(&mut arg2), None, None, None);
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}
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}
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Err(EvalError::VariableNotFound)
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Err(EvalAltResult::ErrorVariableNotFound)
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}
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else if args.len() == 3 {
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let mut arg1 = try!(self.eval_expr(scope, &args[0]));
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@ -404,7 +443,7 @@ impl Engine {
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return self.call_fn(&fn_name, Some(val), Some(&mut arg1), Some(&mut arg2), Some(&mut arg3), None, None);
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}
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}
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Err(EvalError::VariableNotFound)
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Err(EvalAltResult::ErrorVariableNotFound)
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}
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else if args.len() == 4 {
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let mut arg1 = try!(self.eval_expr(scope, &args[0]));
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@ -418,7 +457,7 @@ impl Engine {
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Some(&mut arg4), None);
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}
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}
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Err(EvalError::VariableNotFound)
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Err(EvalAltResult::ErrorVariableNotFound)
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}
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else if args.len() == 5 {
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let mut arg1 = try!(self.eval_expr(scope, &args[0]));
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@ -433,10 +472,10 @@ impl Engine {
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Some(&mut arg4), Some(&mut arg5));
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}
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}
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Err(EvalError::VariableNotFound)
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Err(EvalAltResult::ErrorVariableNotFound)
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}
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else {
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Err(EvalError::FunctionCallNotSupported)
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Err(EvalAltResult::ErrorFunctionCallNotSupported)
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}
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}
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Expr::True => {
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@ -448,17 +487,21 @@ impl Engine {
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}
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}
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fn eval_stmt(&self, scope: &mut Scope, stmt: &Stmt) -> Result<Box<Any>, EvalError> {
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fn eval_stmt(&self, scope: &mut Scope, stmt: &Stmt) -> Result<Box<Any>, EvalAltResult> {
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match *stmt {
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Stmt::Expr(ref e) => {
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self.eval_expr(scope, e)
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}
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Stmt::Block(ref b) => {
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let prev_len = scope.len();
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let mut last_result : Result<Box<Any>, EvalError> = Ok(Box::new(0));
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let mut last_result : Result<Box<Any>, EvalAltResult> = Ok(Box::new(()));
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for s in b.iter() {
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last_result = self.eval_stmt(scope, s)
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last_result = self.eval_stmt(scope, s);
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match last_result {
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Err(x) => {last_result = Err(x); break},
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_ => ()
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}
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}
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while scope.len() > prev_len {
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@ -478,7 +521,7 @@ impl Engine {
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Ok(Box::new(()))
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}
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}
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Err(_) => Err(EvalError::IfGuardMismatch)
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Err(_) => Err(EvalAltResult::ErrorIfGuardMismatch)
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}
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}
|
||||
Stmt::IfElse(ref guard, ref body, ref else_body) => {
|
||||
@ -492,7 +535,7 @@ impl Engine {
|
||||
self.eval_stmt(scope, else_body)
|
||||
}
|
||||
}
|
||||
Err(_) => Err(EvalError::IfGuardMismatch)
|
||||
Err(_) => Err(EvalAltResult::ErrorIfGuardMismatch)
|
||||
}
|
||||
}
|
||||
Stmt::While(ref guard, ref body) => {
|
||||
@ -501,16 +544,26 @@ impl Engine {
|
||||
match guard_result.downcast::<bool>() {
|
||||
Ok(g) => {
|
||||
if *g {
|
||||
try!(self.eval_stmt(scope, body));
|
||||
match self.eval_stmt(scope, body) {
|
||||
Err(EvalAltResult::LoopBreak) => { return Ok(Box::new(())); }
|
||||
Err(x) => { return Err(x); }
|
||||
_ => ()
|
||||
}
|
||||
}
|
||||
else {
|
||||
return Ok(Box::new(()));
|
||||
}
|
||||
}
|
||||
Err(_) => return Err(EvalError::IfGuardMismatch)
|
||||
Err(_) => return Err(EvalAltResult::ErrorIfGuardMismatch)
|
||||
}
|
||||
}
|
||||
}
|
||||
Stmt::Break => return Err(EvalAltResult::LoopBreak),
|
||||
Stmt::Return => return Err(EvalAltResult::Return(Box::new(()))),
|
||||
Stmt::ReturnWithVal(ref a) => {
|
||||
let result = try!(self.eval_expr(scope, a));
|
||||
return Err(EvalAltResult::Return(result));
|
||||
}
|
||||
Stmt::Var(ref name, ref init) => {
|
||||
match init {
|
||||
& Some(ref v) => {
|
||||
@ -526,13 +579,13 @@ impl Engine {
|
||||
}
|
||||
}
|
||||
|
||||
pub fn eval(&mut self, input: String) -> Result<Box<Any>, EvalError> {
|
||||
pub fn eval(&mut self, input: String) -> Result<Box<Any>, EvalAltResult> {
|
||||
let mut scope: Scope = Vec::new();
|
||||
|
||||
self.eval_with_scope(&mut scope, input)
|
||||
}
|
||||
|
||||
pub fn eval_with_scope(&mut self, scope: &mut Scope, input: String) -> Result<Box<Any>, EvalError> {
|
||||
pub fn eval_with_scope(&mut self, scope: &mut Scope, input: String) -> Result<Box<Any>, EvalAltResult> {
|
||||
let tokens = lex(&input);
|
||||
|
||||
let mut peekables = tokens.peekable();
|
||||
@ -540,11 +593,11 @@ impl Engine {
|
||||
|
||||
match tree {
|
||||
Ok((ref os, ref fns)) => {
|
||||
let mut x: Result<Box<Any>, EvalError> = Ok(Box::new(()));
|
||||
let mut x: Result<Box<Any>, EvalAltResult> = Ok(Box::new(()));
|
||||
|
||||
for f in fns {
|
||||
if f.params.len() > 6 {
|
||||
return Err(EvalError::FunctionArityNotSupported);
|
||||
return Err(EvalAltResult::ErrorFunctionArityNotSupported);
|
||||
}
|
||||
let name = f.name.clone();
|
||||
let local_f = f.clone();
|
||||
@ -557,7 +610,7 @@ impl Engine {
|
||||
}
|
||||
x
|
||||
}
|
||||
Err(_) => Err(EvalError::FunctionArgMismatch)
|
||||
Err(_) => Err(EvalAltResult::ErrorFunctionArgMismatch)
|
||||
}
|
||||
}
|
||||
|
||||
@ -716,7 +769,18 @@ fn test_if() {
|
||||
}
|
||||
|
||||
#[test]
|
||||
fn test_while() {
|
||||
let mut engine = Engine::new();
|
||||
|
||||
if let Ok(result) = engine.eval("var x = 0; while x < 10 { x = x + 1; if x > 5 { break } } x".to_string()).unwrap().downcast::<i32>() {
|
||||
assert_eq!(*result, 6);
|
||||
}
|
||||
else {
|
||||
assert!(false);
|
||||
}
|
||||
}
|
||||
|
||||
#[test]
|
||||
fn test_var_scope() {
|
||||
let mut engine = Engine::new();
|
||||
let mut scope: Scope = Vec::new();
|
||||
@ -792,6 +856,13 @@ fn test_internal_fn() {
|
||||
else {
|
||||
assert!(false);
|
||||
}
|
||||
|
||||
if let Ok(result) = engine.eval("fn bob() { return 4; 5 } bob()".to_string()).unwrap().downcast::<i32>() {
|
||||
assert_eq!(*result, 4);
|
||||
}
|
||||
else {
|
||||
assert!(false);
|
||||
}
|
||||
}
|
||||
|
||||
#[test]
|
||||
|
@ -1,7 +1,7 @@
|
||||
use std::any::Any;
|
||||
use std::boxed::Box;
|
||||
|
||||
use engine::{EvalError, Engine, FnType};
|
||||
use engine::{EvalAltResult, Engine, FnType};
|
||||
|
||||
pub trait FnRegister {
|
||||
fn register(self, engine: &mut Engine, name: &str);
|
||||
@ -10,7 +10,7 @@ pub trait FnRegister {
|
||||
impl<T: Any+Clone, U: Any+Clone, V: Any+Clone, W: Any+Clone, X: Any+Clone, Y: Any+Clone, Z: Any+Clone> FnRegister for fn(&mut T, U, V, W, X, Y)->Z {
|
||||
fn register(self, engine: &mut Engine, name: &str) {
|
||||
let wrapped : Box<Fn(&mut Box<Any>, &mut Box<Any>, &mut Box<Any>, &mut Box<Any>, &mut Box<Any>,
|
||||
&mut Box<Any>)->Result<Box<Any>, EvalError>> =
|
||||
&mut Box<Any>)->Result<Box<Any>, EvalAltResult>> =
|
||||
|
||||
Box::new(
|
||||
move |arg1: &mut Box<Any>, arg2: &mut Box<Any>, arg3: &mut Box<Any>, arg4: &mut Box<Any>,
|
||||
@ -26,7 +26,7 @@ impl<T: Any+Clone, U: Any+Clone, V: Any+Clone, W: Any+Clone, X: Any+Clone, Y: An
|
||||
match (inside1, inside2, inside3, inside4, inside5, inside6) {
|
||||
(Some(b), Some(c), Some(d), Some(e), Some(f), Some(g)) => Ok(Box::new(self(b, c.clone(), d.clone(),
|
||||
e.clone(), f.clone(), g.clone())) as Box<Any>),
|
||||
_ => Err(EvalError::FunctionArgMismatch)
|
||||
_ => Err(EvalAltResult::ErrorFunctionArgMismatch)
|
||||
}
|
||||
}
|
||||
);
|
||||
@ -39,7 +39,7 @@ impl<T: Any+Clone, U: Any+Clone, V: Any+Clone, W: Any+Clone, X: Any+Clone, Y: An
|
||||
impl<T: Any+Clone, U: Any+Clone, V: Any+Clone, W: Any+Clone, X: Any+Clone, Y: Any+Clone, Z: Any+Clone> FnRegister for fn(T, U, V, W, X, Y)->Z {
|
||||
fn register(self, engine: &mut Engine, name: &str) {
|
||||
let wrapped : Box<Fn(&mut Box<Any>, &mut Box<Any>, &mut Box<Any>, &mut Box<Any>, &mut Box<Any>,
|
||||
&mut Box<Any>)->Result<Box<Any>, EvalError>> =
|
||||
&mut Box<Any>)->Result<Box<Any>, EvalAltResult>> =
|
||||
|
||||
Box::new(
|
||||
move |arg1: &mut Box<Any>, arg2: &mut Box<Any>, arg3: &mut Box<Any>, arg4: &mut Box<Any>,
|
||||
@ -55,7 +55,7 @@ impl<T: Any+Clone, U: Any+Clone, V: Any+Clone, W: Any+Clone, X: Any+Clone, Y: An
|
||||
match (inside1, inside2, inside3, inside4, inside5, inside6) {
|
||||
(Some(b), Some(c), Some(d), Some(e), Some(f), Some(g)) => Ok(Box::new(self(b.clone(), c.clone(), d.clone(),
|
||||
e.clone(), f.clone(), g.clone())) as Box<Any>),
|
||||
_ => Err(EvalError::FunctionArgMismatch)
|
||||
_ => Err(EvalAltResult::ErrorFunctionArgMismatch)
|
||||
}
|
||||
}
|
||||
);
|
||||
@ -67,7 +67,7 @@ impl<T: Any+Clone, U: Any+Clone, V: Any+Clone, W: Any+Clone, X: Any+Clone, Y: An
|
||||
|
||||
impl<T: Any+Clone, U: Any+Clone, V: Any+Clone, W: Any+Clone, X: Any+Clone, Y: Any+Clone> FnRegister for fn(&mut T, U, V, W, X)->Y {
|
||||
fn register(self, engine: &mut Engine, name: &str) {
|
||||
let wrapped : Box<Fn(&mut Box<Any>, &mut Box<Any>, &mut Box<Any>, &mut Box<Any>, &mut Box<Any>)->Result<Box<Any>, EvalError>> =
|
||||
let wrapped : Box<Fn(&mut Box<Any>, &mut Box<Any>, &mut Box<Any>, &mut Box<Any>, &mut Box<Any>)->Result<Box<Any>, EvalAltResult>> =
|
||||
Box::new(
|
||||
move |arg1: &mut Box<Any>, arg2: &mut Box<Any>, arg3: &mut Box<Any>, arg4: &mut Box<Any>,
|
||||
arg5: &mut Box<Any>| {
|
||||
@ -81,7 +81,7 @@ impl<T: Any+Clone, U: Any+Clone, V: Any+Clone, W: Any+Clone, X: Any+Clone, Y: An
|
||||
match (inside1, inside2, inside3, inside4, inside5) {
|
||||
(Some(b), Some(c), Some(d), Some(e), Some(f)) => Ok(Box::new(self(b, c.clone(), d.clone(),
|
||||
e.clone(), f.clone())) as Box<Any>),
|
||||
_ => Err(EvalError::FunctionArgMismatch)
|
||||
_ => Err(EvalAltResult::ErrorFunctionArgMismatch)
|
||||
}
|
||||
}
|
||||
);
|
||||
@ -93,7 +93,7 @@ impl<T: Any+Clone, U: Any+Clone, V: Any+Clone, W: Any+Clone, X: Any+Clone, Y: An
|
||||
|
||||
impl<T: Any+Clone, U: Any+Clone, V: Any+Clone, W: Any+Clone, X: Any+Clone, Y: Any+Clone> FnRegister for fn(T, U, V, W, X)->Y {
|
||||
fn register(self, engine: &mut Engine, name: &str) {
|
||||
let wrapped : Box<Fn(&mut Box<Any>, &mut Box<Any>, &mut Box<Any>, &mut Box<Any>, &mut Box<Any>)->Result<Box<Any>, EvalError>> =
|
||||
let wrapped : Box<Fn(&mut Box<Any>, &mut Box<Any>, &mut Box<Any>, &mut Box<Any>, &mut Box<Any>)->Result<Box<Any>, EvalAltResult>> =
|
||||
Box::new(
|
||||
move |arg1: &mut Box<Any>, arg2: &mut Box<Any>, arg3: &mut Box<Any>, arg4: &mut Box<Any>,
|
||||
arg5: &mut Box<Any>| {
|
||||
@ -107,7 +107,7 @@ impl<T: Any+Clone, U: Any+Clone, V: Any+Clone, W: Any+Clone, X: Any+Clone, Y: An
|
||||
match (inside1, inside2, inside3, inside4, inside5) {
|
||||
(Some(b), Some(c), Some(d), Some(e), Some(f)) => Ok(Box::new(self(b.clone(), c.clone(), d.clone(),
|
||||
e.clone(), f.clone())) as Box<Any>),
|
||||
_ => Err(EvalError::FunctionArgMismatch)
|
||||
_ => Err(EvalAltResult::ErrorFunctionArgMismatch)
|
||||
}
|
||||
}
|
||||
);
|
||||
@ -119,7 +119,7 @@ impl<T: Any+Clone, U: Any+Clone, V: Any+Clone, W: Any+Clone, X: Any+Clone, Y: An
|
||||
|
||||
impl<T: Any+Clone, U: Any+Clone, V: Any+Clone, W: Any+Clone, X: Any+Clone> FnRegister for fn(&mut T, U, V, W)->X {
|
||||
fn register(self, engine: &mut Engine, name: &str) {
|
||||
let wrapped : Box<Fn(&mut Box<Any>, &mut Box<Any>, &mut Box<Any>, &mut Box<Any>)->Result<Box<Any>, EvalError>> =
|
||||
let wrapped : Box<Fn(&mut Box<Any>, &mut Box<Any>, &mut Box<Any>, &mut Box<Any>)->Result<Box<Any>, EvalAltResult>> =
|
||||
Box::new(
|
||||
move |arg1: &mut Box<Any>, arg2: &mut Box<Any>, arg3: &mut Box<Any>, arg4: &mut Box<Any>| {
|
||||
let inside1 = (*arg1).downcast_mut() as Option<&mut T>;
|
||||
@ -129,7 +129,7 @@ impl<T: Any+Clone, U: Any+Clone, V: Any+Clone, W: Any+Clone, X: Any+Clone> FnReg
|
||||
|
||||
match (inside1, inside2, inside3, inside4) {
|
||||
(Some(b), Some(c), Some(d), Some(e)) => Ok(Box::new(self(b, c.clone(), d.clone(), e.clone())) as Box<Any>),
|
||||
_ => Err(EvalError::FunctionArgMismatch)
|
||||
_ => Err(EvalAltResult::ErrorFunctionArgMismatch)
|
||||
}
|
||||
}
|
||||
);
|
||||
@ -141,7 +141,7 @@ impl<T: Any+Clone, U: Any+Clone, V: Any+Clone, W: Any+Clone, X: Any+Clone> FnReg
|
||||
|
||||
impl<T: Any+Clone, U: Any+Clone, V: Any+Clone, W: Any+Clone, X: Any+Clone> FnRegister for fn(T, U, V, W)->X {
|
||||
fn register(self, engine: &mut Engine, name: &str) {
|
||||
let wrapped : Box<Fn(&mut Box<Any>, &mut Box<Any>, &mut Box<Any>, &mut Box<Any>)->Result<Box<Any>, EvalError>> =
|
||||
let wrapped : Box<Fn(&mut Box<Any>, &mut Box<Any>, &mut Box<Any>, &mut Box<Any>)->Result<Box<Any>, EvalAltResult>> =
|
||||
Box::new(
|
||||
move |arg1: &mut Box<Any>, arg2: &mut Box<Any>, arg3: &mut Box<Any>, arg4: &mut Box<Any>| {
|
||||
let inside1 = (*arg1).downcast_mut() as Option<&mut T>;
|
||||
@ -151,7 +151,7 @@ impl<T: Any+Clone, U: Any+Clone, V: Any+Clone, W: Any+Clone, X: Any+Clone> FnReg
|
||||
|
||||
match (inside1, inside2, inside3, inside4) {
|
||||
(Some(b), Some(c), Some(d), Some(e)) => Ok(Box::new(self(b.clone(), c.clone(), d.clone(), e.clone())) as Box<Any>),
|
||||
_ => Err(EvalError::FunctionArgMismatch)
|
||||
_ => Err(EvalAltResult::ErrorFunctionArgMismatch)
|
||||
}
|
||||
}
|
||||
);
|
||||
@ -163,7 +163,7 @@ impl<T: Any+Clone, U: Any+Clone, V: Any+Clone, W: Any+Clone, X: Any+Clone> FnReg
|
||||
|
||||
impl<T: Any+Clone, U: Any+Clone, V: Any+Clone, W: Any+Clone> FnRegister for fn(&mut T, U, V)->W {
|
||||
fn register(self, engine: &mut Engine, name: &str) {
|
||||
let wrapped : Box<Fn(&mut Box<Any>, &mut Box<Any>, &mut Box<Any>)->Result<Box<Any>, EvalError>> =
|
||||
let wrapped : Box<Fn(&mut Box<Any>, &mut Box<Any>, &mut Box<Any>)->Result<Box<Any>, EvalAltResult>> =
|
||||
Box::new(
|
||||
move |arg1: &mut Box<Any>, arg2: &mut Box<Any>, arg3: &mut Box<Any>| {
|
||||
let inside1 = (*arg1).downcast_mut() as Option<&mut T>;
|
||||
@ -172,7 +172,7 @@ impl<T: Any+Clone, U: Any+Clone, V: Any+Clone, W: Any+Clone> FnRegister for fn(&
|
||||
|
||||
match (inside1, inside2, inside3) {
|
||||
(Some(b), Some(c), Some(d)) => Ok(Box::new(self(b, c.clone(), d.clone())) as Box<Any>),
|
||||
_ => Err(EvalError::FunctionArgMismatch)
|
||||
_ => Err(EvalAltResult::ErrorFunctionArgMismatch)
|
||||
}
|
||||
}
|
||||
);
|
||||
@ -184,7 +184,7 @@ impl<T: Any+Clone, U: Any+Clone, V: Any+Clone, W: Any+Clone> FnRegister for fn(&
|
||||
|
||||
impl<T: Any+Clone, U: Any+Clone, V: Any+Clone, W: Any+Clone> FnRegister for fn(T, U, V)->W {
|
||||
fn register(self, engine: &mut Engine, name: &str) {
|
||||
let wrapped : Box<Fn(&mut Box<Any>, &mut Box<Any>, &mut Box<Any>)->Result<Box<Any>, EvalError>> =
|
||||
let wrapped : Box<Fn(&mut Box<Any>, &mut Box<Any>, &mut Box<Any>)->Result<Box<Any>, EvalAltResult>> =
|
||||
Box::new(
|
||||
move |arg1: &mut Box<Any>, arg2: &mut Box<Any>, arg3: &mut Box<Any>| {
|
||||
let inside1 = (*arg1).downcast_mut() as Option<&mut T>;
|
||||
@ -193,7 +193,7 @@ impl<T: Any+Clone, U: Any+Clone, V: Any+Clone, W: Any+Clone> FnRegister for fn(T
|
||||
|
||||
match (inside1, inside2, inside3) {
|
||||
(Some(b), Some(c), Some(d)) => Ok(Box::new(self(b.clone(), c.clone(), d.clone())) as Box<Any>),
|
||||
_ => Err(EvalError::FunctionArgMismatch)
|
||||
_ => Err(EvalAltResult::ErrorFunctionArgMismatch)
|
||||
}
|
||||
}
|
||||
);
|
||||
@ -205,7 +205,7 @@ impl<T: Any+Clone, U: Any+Clone, V: Any+Clone, W: Any+Clone> FnRegister for fn(T
|
||||
|
||||
impl<T: Any+Clone, U: Any+Clone, V: Any+Clone> FnRegister for fn(&mut T, U)->V {
|
||||
fn register(self, engine: &mut Engine, name: &str) {
|
||||
let wrapped : Box<Fn(&mut Box<Any>, &mut Box<Any>)->Result<Box<Any>, EvalError>> =
|
||||
let wrapped : Box<Fn(&mut Box<Any>, &mut Box<Any>)->Result<Box<Any>, EvalAltResult>> =
|
||||
Box::new(
|
||||
move |arg1: &mut Box<Any>, arg2: &mut Box<Any>| {
|
||||
let inside1 = (*arg1).downcast_mut() as Option<&mut T>;
|
||||
@ -213,7 +213,7 @@ impl<T: Any+Clone, U: Any+Clone, V: Any+Clone> FnRegister for fn(&mut T, U)->V {
|
||||
|
||||
match (inside1, inside2) {
|
||||
(Some(b), Some(c)) => Ok(Box::new(self(b, c.clone())) as Box<Any>),
|
||||
_ => Err(EvalError::FunctionArgMismatch)
|
||||
_ => Err(EvalAltResult::ErrorFunctionArgMismatch)
|
||||
}
|
||||
}
|
||||
);
|
||||
@ -225,7 +225,7 @@ impl<T: Any+Clone, U: Any+Clone, V: Any+Clone> FnRegister for fn(&mut T, U)->V {
|
||||
|
||||
impl<T: Any+Clone, U: Any+Clone, V: Any+Clone> FnRegister for fn(T, U)->V {
|
||||
fn register(self, engine: &mut Engine, name: &str) {
|
||||
let wrapped : Box<Fn(&mut Box<Any>, &mut Box<Any>)->Result<Box<Any>, EvalError>> =
|
||||
let wrapped : Box<Fn(&mut Box<Any>, &mut Box<Any>)->Result<Box<Any>, EvalAltResult>> =
|
||||
Box::new(
|
||||
move |arg1: &mut Box<Any>, arg2: &mut Box<Any>| {
|
||||
let inside1 = (*arg1).downcast_mut() as Option<&mut T>;
|
||||
@ -233,7 +233,7 @@ impl<T: Any+Clone, U: Any+Clone, V: Any+Clone> FnRegister for fn(T, U)->V {
|
||||
|
||||
match (inside1, inside2) {
|
||||
(Some(b), Some(c)) => Ok(Box::new(self(b.clone(), c.clone())) as Box<Any>),
|
||||
_ => Err(EvalError::FunctionArgMismatch)
|
||||
_ => Err(EvalAltResult::ErrorFunctionArgMismatch)
|
||||
}
|
||||
}
|
||||
);
|
||||
@ -245,14 +245,14 @@ impl<T: Any+Clone, U: Any+Clone, V: Any+Clone> FnRegister for fn(T, U)->V {
|
||||
|
||||
impl<T: Any+Clone, U: Any+Clone> FnRegister for fn(&mut T)->U {
|
||||
fn register(self, engine: &mut Engine, name: &str) {
|
||||
let wrapped : Box<Fn(&mut Box<Any>)->Result<Box<Any>, EvalError>> =
|
||||
let wrapped : Box<Fn(&mut Box<Any>)->Result<Box<Any>, EvalAltResult>> =
|
||||
Box::new(
|
||||
move |arg: &mut Box<Any>| {
|
||||
let inside = (*arg).downcast_mut() as Option<&mut T>;
|
||||
|
||||
match inside {
|
||||
Some(b) => Ok(Box::new(self(b)) as Box<Any>),
|
||||
None => Err(EvalError::FunctionArgMismatch)
|
||||
None => Err(EvalAltResult::ErrorFunctionArgMismatch)
|
||||
}
|
||||
}
|
||||
);
|
||||
@ -264,13 +264,13 @@ impl<T: Any+Clone, U: Any+Clone> FnRegister for fn(&mut T)->U {
|
||||
|
||||
impl<T: Any+Clone, U: Any+Clone> FnRegister for fn(T)->U {
|
||||
fn register(self, engine: &mut Engine, name: &str) {
|
||||
let wrapped : Box<Fn(&mut Box<Any>)->Result<Box<Any>, EvalError>> =
|
||||
let wrapped : Box<Fn(&mut Box<Any>)->Result<Box<Any>, EvalAltResult>> =
|
||||
Box::new(
|
||||
move |arg: &mut Box<Any>| {
|
||||
let inside = (*arg).downcast_mut() as Option<&mut T>;
|
||||
match inside {
|
||||
Some(b) => Ok(Box::new(self(b.clone())) as Box<Any>),
|
||||
None => Err(EvalError::FunctionArgMismatch)
|
||||
None => Err(EvalAltResult::ErrorFunctionArgMismatch)
|
||||
}
|
||||
}
|
||||
);
|
||||
@ -282,7 +282,7 @@ impl<T: Any+Clone, U: Any+Clone> FnRegister for fn(T)->U {
|
||||
|
||||
impl<T: Any+Clone> FnRegister for fn()->T {
|
||||
fn register(self, engine: &mut Engine, name: &str) {
|
||||
let wrapped : Box<Fn()->Result<Box<Any>, EvalError>> =
|
||||
let wrapped : Box<Fn()->Result<Box<Any>, EvalAltResult>> =
|
||||
Box::new(
|
||||
move || { Ok(Box::new(self()) as Box<Any>) }
|
||||
);
|
||||
|
@ -18,7 +18,6 @@ mod parser;
|
||||
// * How it works
|
||||
// * Vectors
|
||||
// * Return
|
||||
// * Break
|
||||
// * Tighten parser?
|
||||
// * Errors with positions?
|
||||
// * Remove empty box values?
|
||||
|
@ -85,7 +85,7 @@ pub struct FnDef {
|
||||
|
||||
#[derive(Debug, Clone)]
|
||||
pub enum Stmt { If(Box<Expr>, Box<Stmt>), IfElse(Box<Expr>, Box<Stmt>, Box<Stmt>), While(Box<Expr>, Box<Stmt>),
|
||||
Var(String, Option<Box<Expr>>), Block(Box<Vec<Stmt>>), Expr(Box<Expr>) }
|
||||
Var(String, Option<Box<Expr>>), Block(Box<Vec<Stmt>>), Expr(Box<Expr>), Break, Return, ReturnWithVal(Box<Expr>) }
|
||||
|
||||
#[derive(Debug, Clone)]
|
||||
pub enum Expr { IntConst(i32), Identifier(String), StringConst(String), FnCall(String, Box<Vec<Expr>>),
|
||||
@ -95,7 +95,7 @@ pub enum Expr { IntConst(i32), Identifier(String), StringConst(String), FnCall(S
|
||||
pub enum Token { IntConst(i32), Identifier(String), StringConst(String), LCurly, RCurly, LParen, RParen, LSquare, RSquare,
|
||||
Plus, Minus, Multiply, Divide, Semicolon, Colon, Comma, Period, Equals, True, False, Var, If, Else, While,
|
||||
LessThan, GreaterThan, Bang, LessThanEqual, GreaterThanEqual, EqualTo, NotEqualTo, Pipe, Or, Ampersand, And, Fn,
|
||||
LexErr(LexError) }
|
||||
Break, Return, LexErr(LexError) }
|
||||
|
||||
pub struct TokenIterator<'a> {
|
||||
char_stream: Peekable<Chars<'a>>
|
||||
@ -157,6 +157,12 @@ impl<'a> Iterator for TokenIterator<'a> {
|
||||
else if out == "while" {
|
||||
return Some(Token::While);
|
||||
}
|
||||
else if out == "break" {
|
||||
return Some(Token::Break);
|
||||
}
|
||||
else if out == "return" {
|
||||
return Some(Token::Return);
|
||||
}
|
||||
else if out == "fn" {
|
||||
return Some(Token::Fn);
|
||||
}
|
||||
@ -569,6 +575,14 @@ fn parse_stmt<'a>(input: &mut Peekable<TokenIterator<'a>>) -> Result<Stmt, Parse
|
||||
match input.peek() {
|
||||
Some(& Token::If) => parse_if(input),
|
||||
Some(& Token::While) => parse_while(input),
|
||||
Some(& Token::Break) => {input.next(); Ok(Stmt::Break)},
|
||||
Some(& Token::Return) => {
|
||||
input.next();
|
||||
match input.peek() {
|
||||
Some(& Token::Semicolon) => Ok(Stmt::Return),
|
||||
_ => {let ret = try!(parse_expr(input)); Ok(Stmt::ReturnWithVal(Box::new(ret))) }
|
||||
}
|
||||
}
|
||||
Some(& Token::LCurly) => parse_block(input),
|
||||
Some(& Token::Var) => parse_var(input),
|
||||
_ => parse_expr_stmt(input)
|
||||
|
Loading…
Reference in New Issue
Block a user