758 lines
27 KiB
Rust
758 lines
27 KiB
Rust
use crate::any::Dynamic;
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use crate::calc_fn_hash;
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use crate::engine::{
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Engine, FnAny, FnCallArgs, FunctionsLib, KEYWORD_DEBUG, KEYWORD_EVAL, KEYWORD_PRINT,
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KEYWORD_TYPE_OF,
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};
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use crate::packages::PackageLibrary;
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use crate::parser::{map_dynamic_to_expr, Expr, FnDef, ReturnType, Stmt, AST};
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use crate::result::EvalAltResult;
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use crate::scope::{Entry as ScopeEntry, EntryType as ScopeEntryType, Scope};
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use crate::token::Position;
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use crate::stdlib::{
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boxed::Box,
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collections::HashMap,
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string::{String, ToString},
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vec,
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vec::Vec,
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};
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/// Level of optimization performed.
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///
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/// Not available under the `no_optimize` feature.
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#[derive(Debug, Eq, PartialEq, Hash, Clone, Copy)]
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pub enum OptimizationLevel {
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/// No optimization performed.
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None,
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/// Only perform simple optimizations without evaluating functions.
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Simple,
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/// Full optimizations performed, including evaluating functions.
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/// Take care that this may cause side effects as it essentially assumes that all functions are pure.
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Full,
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}
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impl OptimizationLevel {
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/// Is the `OptimizationLevel` None.
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pub fn is_none(self) -> bool {
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self == Self::None
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}
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/// Is the `OptimizationLevel` Full.
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pub fn is_full(self) -> bool {
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self == Self::Full
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}
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}
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/// Mutable state throughout an optimization pass.
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struct State<'a> {
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/// Has the AST been changed during this pass?
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changed: bool,
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/// Collection of constants to use for eager function evaluations.
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constants: Vec<(String, Expr)>,
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/// An `Engine` instance for eager function evaluation.
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engine: &'a Engine,
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/// Library of script-defined functions.
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fn_lib: &'a [(&'a str, usize)],
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/// Optimization level.
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optimization_level: OptimizationLevel,
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}
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impl<'a> State<'a> {
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/// Create a new State.
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pub fn new(
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engine: &'a Engine,
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fn_lib: &'a [(&'a str, usize)],
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level: OptimizationLevel,
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) -> Self {
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Self {
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changed: false,
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constants: vec![],
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engine,
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fn_lib,
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optimization_level: level,
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}
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}
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/// Reset the state from dirty to clean.
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pub fn reset(&mut self) {
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self.changed = false;
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}
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/// Set the AST state to be dirty (i.e. changed).
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pub fn set_dirty(&mut self) {
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self.changed = true;
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}
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/// Is the AST dirty (i.e. changed)?
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pub fn is_dirty(&self) -> bool {
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self.changed
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}
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/// Does a constant exist?
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pub fn contains_constant(&self, name: &str) -> bool {
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self.constants.iter().any(|(n, _)| n == name)
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}
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/// Prune the list of constants back to a specified size.
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pub fn restore_constants(&mut self, len: usize) {
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self.constants.truncate(len)
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}
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/// Add a new constant to the list.
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pub fn push_constant(&mut self, name: &str, value: Expr) {
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self.constants.push((name.to_string(), value))
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}
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/// Look up a constant from the list.
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pub fn find_constant(&self, name: &str) -> Option<&Expr> {
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for (n, expr) in self.constants.iter().rev() {
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if n == name {
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return Some(expr);
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}
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}
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None
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}
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}
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/// Call a registered function
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fn call_fn(
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packages: &Vec<PackageLibrary>,
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functions: &HashMap<u64, Box<FnAny>>,
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fn_name: &str,
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args: &mut FnCallArgs,
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pos: Position,
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) -> Result<Option<Dynamic>, Box<EvalAltResult>> {
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// Search built-in's and external functions
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let hash = calc_fn_hash(fn_name, args.iter().map(|a| a.type_id()));
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functions
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.get(&hash)
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.or_else(|| {
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packages
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.iter()
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.find(|p| p.functions.contains_key(&hash))
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.and_then(|p| p.functions.get(&hash))
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})
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.map(|func| func(args, pos))
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.transpose()
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}
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/// Optimize a statement.
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fn optimize_stmt<'a>(stmt: Stmt, state: &mut State<'a>, preserve_result: bool) -> Stmt {
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match stmt {
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// if expr { Noop }
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Stmt::IfThenElse(expr, if_block, None) if matches!(*if_block, Stmt::Noop(_)) => {
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state.set_dirty();
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let pos = expr.position();
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let expr = optimize_expr(*expr, state);
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if preserve_result {
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// -> { expr, Noop }
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Stmt::Block(vec![Stmt::Expr(Box::new(expr)), *if_block], pos)
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} else {
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// -> expr
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Stmt::Expr(Box::new(expr))
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}
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}
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// if expr { if_block }
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Stmt::IfThenElse(expr, if_block, None) => match *expr {
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// if false { if_block } -> Noop
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Expr::False(pos) => {
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state.set_dirty();
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Stmt::Noop(pos)
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}
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// if true { if_block } -> if_block
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Expr::True(_) => optimize_stmt(*if_block, state, true),
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// if expr { if_block }
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expr => Stmt::IfThenElse(
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Box::new(optimize_expr(expr, state)),
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Box::new(optimize_stmt(*if_block, state, true)),
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None,
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),
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},
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// if expr { if_block } else { else_block }
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Stmt::IfThenElse(expr, if_block, Some(else_block)) => match *expr {
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// if false { if_block } else { else_block } -> else_block
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Expr::False(_) => optimize_stmt(*else_block, state, true),
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// if true { if_block } else { else_block } -> if_block
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Expr::True(_) => optimize_stmt(*if_block, state, true),
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// if expr { if_block } else { else_block }
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expr => Stmt::IfThenElse(
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Box::new(optimize_expr(expr, state)),
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Box::new(optimize_stmt(*if_block, state, true)),
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match optimize_stmt(*else_block, state, true) {
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Stmt::Noop(_) => None, // Noop -> no else block
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stmt => Some(Box::new(stmt)),
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},
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),
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},
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// while expr { block }
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Stmt::While(expr, block) => match *expr {
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// while false { block } -> Noop
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Expr::False(pos) => {
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state.set_dirty();
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Stmt::Noop(pos)
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}
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// while true { block } -> loop { block }
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Expr::True(_) => Stmt::Loop(Box::new(optimize_stmt(*block, state, false))),
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// while expr { block }
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expr => match optimize_stmt(*block, state, false) {
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// while expr { break; } -> { expr; }
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Stmt::Break(pos) => {
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// Only a single break statement - turn into running the guard expression once
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state.set_dirty();
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let mut statements = vec![Stmt::Expr(Box::new(optimize_expr(expr, state)))];
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if preserve_result {
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statements.push(Stmt::Noop(pos))
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}
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Stmt::Block(statements, pos)
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}
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// while expr { block }
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stmt => Stmt::While(Box::new(optimize_expr(expr, state)), Box::new(stmt)),
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},
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},
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// loop { block }
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Stmt::Loop(block) => match optimize_stmt(*block, state, false) {
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// loop { break; } -> Noop
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Stmt::Break(pos) => {
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// Only a single break statement
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state.set_dirty();
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Stmt::Noop(pos)
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}
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// loop { block }
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stmt => Stmt::Loop(Box::new(stmt)),
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},
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// for id in expr { block }
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Stmt::For(id, expr, block) => Stmt::For(
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id,
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Box::new(optimize_expr(*expr, state)),
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Box::new(optimize_stmt(*block, state, false)),
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),
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// let id = expr;
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Stmt::Let(id, Some(expr), pos) => {
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Stmt::Let(id, Some(Box::new(optimize_expr(*expr, state))), pos)
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}
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// let id;
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Stmt::Let(_, None, _) => stmt,
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// import expr as id;
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Stmt::Import(expr, id, pos) => Stmt::Import(Box::new(optimize_expr(*expr, state)), id, pos),
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// { block }
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Stmt::Block(block, pos) => {
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let orig_len = block.len(); // Original number of statements in the block, for change detection
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let orig_constants_len = state.constants.len(); // Original number of constants in the state, for restore later
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// Optimize each statement in the block
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let mut result: Vec<_> = block
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.into_iter()
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.map(|stmt| match stmt {
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// Add constant into the state
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Stmt::Const(name, value, pos) => {
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state.push_constant(&name, *value);
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state.set_dirty();
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Stmt::Noop(pos) // No need to keep constants
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}
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// Optimize the statement
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_ => optimize_stmt(stmt, state, preserve_result),
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})
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.collect();
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// Remove all raw expression statements that are pure except for the very last statement
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let last_stmt = if preserve_result { result.pop() } else { None };
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result.retain(|stmt| !stmt.is_pure());
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if let Some(stmt) = last_stmt {
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result.push(stmt);
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}
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// Remove all let/import statements at the end of a block - the new variables will go away anyway.
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// But be careful only remove ones that have no initial values or have values that are pure expressions,
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// otherwise there may be side effects.
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let mut removed = false;
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while let Some(expr) = result.pop() {
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match expr {
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Stmt::Let(_, None, _) => removed = true,
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Stmt::Let(_, Some(val_expr), _) => removed = val_expr.is_pure(),
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Stmt::Import(expr, _, _) => removed = expr.is_pure(),
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_ => {
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result.push(expr);
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break;
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}
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}
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}
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if preserve_result {
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if removed {
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result.push(Stmt::Noop(pos))
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}
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// Optimize all the statements again
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result = result
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.into_iter()
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.rev()
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.enumerate()
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.map(|(i, s)| optimize_stmt(s, state, i == 0))
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.rev()
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.collect();
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}
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// Remove everything following the the first return/throw
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let mut dead_code = false;
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result.retain(|stmt| {
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if dead_code {
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return false;
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}
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match stmt {
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Stmt::ReturnWithVal(_, _, _) | Stmt::Break(_) => {
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dead_code = true;
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}
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_ => (),
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}
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true
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});
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// Change detection
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if orig_len != result.len() {
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state.set_dirty();
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}
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// Pop the stack and remove all the local constants
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state.restore_constants(orig_constants_len);
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match result[..] {
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// No statements in block - change to No-op
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[] => {
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state.set_dirty();
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Stmt::Noop(pos)
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}
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// Only one let/import statement - leave it alone
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[Stmt::Let(_, _, _)] | [Stmt::Import(_, _, _)] => Stmt::Block(result, pos),
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// Only one statement - promote
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[_] => {
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state.set_dirty();
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result.remove(0)
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}
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_ => Stmt::Block(result, pos),
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}
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}
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// expr;
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Stmt::Expr(expr) => Stmt::Expr(Box::new(optimize_expr(*expr, state))),
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// return expr;
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Stmt::ReturnWithVal(Some(expr), is_return, pos) => {
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Stmt::ReturnWithVal(Some(Box::new(optimize_expr(*expr, state))), is_return, pos)
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}
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// All other statements - skip
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stmt => stmt,
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}
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}
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/// Optimize an expression.
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fn optimize_expr<'a>(expr: Expr, state: &mut State<'a>) -> Expr {
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// These keywords are handled specially
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const DONT_EVAL_KEYWORDS: [&str; 3] = [KEYWORD_PRINT, KEYWORD_DEBUG, KEYWORD_EVAL];
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match expr {
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// ( stmt )
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Expr::Stmt(stmt, pos) => match optimize_stmt(*stmt, state, true) {
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// ( Noop ) -> ()
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Stmt::Noop(_) => {
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state.set_dirty();
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Expr::Unit(pos)
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}
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// ( expr ) -> expr
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Stmt::Expr(expr) => {
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state.set_dirty();
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*expr
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}
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// ( stmt )
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stmt => Expr::Stmt(Box::new(stmt), pos),
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},
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// id = expr
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Expr::Assignment(id, expr, pos) => match *expr {
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//id = id2 = expr2
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Expr::Assignment(id2, expr2, pos2) => match (*id, *id2) {
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// var = var = expr2 -> var = expr2
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(Expr::Variable(var, None, sp, _), Expr::Variable(var2, None, sp2, _))
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if var == var2 && sp == sp2 =>
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{
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// Assignment to the same variable - fold
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state.set_dirty();
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Expr::Assignment(Box::new(Expr::Variable(var, None, sp, pos)), Box::new(optimize_expr(*expr2, state)), pos)
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}
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// id1 = id2 = expr2
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(id1, id2) => Expr::Assignment(
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Box::new(id1),
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Box::new(Expr::Assignment(
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Box::new(id2),
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Box::new(optimize_expr(*expr2, state)),
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pos2,
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)),
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pos,
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),
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},
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// id = expr
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expr => Expr::Assignment(id, Box::new(optimize_expr(expr, state)), pos),
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},
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// lhs.rhs
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#[cfg(not(feature = "no_object"))]
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Expr::Dot(lhs, rhs, pos) => match (*lhs, *rhs) {
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// map.string
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(Expr::Map(items, pos), Expr::Property(s, _)) if items.iter().all(|(_, x, _)| x.is_pure()) => {
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// Map literal where everything is pure - promote the indexed item.
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// All other items can be thrown away.
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state.set_dirty();
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items.into_iter().find(|(name, _, _)| name == &s)
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.map(|(_, expr, _)| expr.set_position(pos))
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.unwrap_or_else(|| Expr::Unit(pos))
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}
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// lhs.rhs
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(lhs, rhs) => Expr::Dot(
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Box::new(optimize_expr(lhs, state)),
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Box::new(optimize_expr(rhs, state)),
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pos,
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)
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}
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// lhs[rhs]
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#[cfg(not(feature = "no_index"))]
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Expr::Index(lhs, rhs, pos) => match (*lhs, *rhs) {
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// array[int]
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(Expr::Array(mut items, pos), Expr::IntegerConstant(i, _))
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if i >= 0 && (i as usize) < items.len() && items.iter().all(Expr::is_pure) =>
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{
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// Array literal where everything is pure - promote the indexed item.
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// All other items can be thrown away.
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state.set_dirty();
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items.remove(i as usize).set_position(pos)
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}
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// map[string]
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(Expr::Map(items, pos), Expr::StringConstant(s, _)) if items.iter().all(|(_, x, _)| x.is_pure()) => {
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// Map literal where everything is pure - promote the indexed item.
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// All other items can be thrown away.
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state.set_dirty();
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items.into_iter().find(|(name, _, _)| name == &s)
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.map(|(_, expr, _)| expr.set_position(pos))
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.unwrap_or_else(|| Expr::Unit(pos))
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}
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// string[int]
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(Expr::StringConstant(s, pos), Expr::IntegerConstant(i, _)) if i >= 0 && (i as usize) < s.chars().count() => {
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// String literal indexing - get the character
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state.set_dirty();
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Expr::CharConstant(s.chars().nth(i as usize).expect("should get char"), pos)
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}
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// lhs[rhs]
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(lhs, rhs) => Expr::Index(
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Box::new(optimize_expr(lhs, state)),
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Box::new(optimize_expr(rhs, state)),
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pos,
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),
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},
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// [ items .. ]
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#[cfg(not(feature = "no_index"))]
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Expr::Array(items, pos) => Expr::Array(items
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.into_iter()
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.map(|expr| optimize_expr(expr, state))
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.collect(), pos),
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// [ items .. ]
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#[cfg(not(feature = "no_object"))]
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Expr::Map(items, pos) => Expr::Map(items
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.into_iter()
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.map(|(key, expr, pos)| (key, optimize_expr(expr, state), pos))
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.collect(), pos),
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// lhs in rhs
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Expr::In(lhs, rhs, pos) => match (*lhs, *rhs) {
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// "xxx" in "xxxxx"
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(Expr::StringConstant(lhs, pos), Expr::StringConstant(rhs, _)) => {
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state.set_dirty();
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if rhs.contains(&lhs) {
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Expr::True(pos)
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} else {
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Expr::False(pos)
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}
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}
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// 'x' in "xxxxx"
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(Expr::CharConstant(lhs, pos), Expr::StringConstant(rhs, _)) => {
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state.set_dirty();
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if rhs.contains(&lhs.to_string()) {
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Expr::True(pos)
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} else {
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Expr::False(pos)
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}
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}
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// "xxx" in #{...}
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(Expr::StringConstant(lhs, pos), Expr::Map(items, _)) => {
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state.set_dirty();
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if items.iter().find(|(name, _, _)| name == &lhs).is_some() {
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Expr::True(pos)
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} else {
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Expr::False(pos)
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}
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}
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// 'x' in #{...}
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(Expr::CharConstant(lhs, pos), Expr::Map(items, _)) => {
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state.set_dirty();
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let lhs = lhs.to_string();
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if items.iter().find(|(name, _, _)| name == &lhs).is_some() {
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Expr::True(pos)
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} else {
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Expr::False(pos)
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}
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|
}
|
|
// lhs in rhs
|
|
(lhs, rhs) => Expr::In(
|
|
Box::new(optimize_expr(lhs, state)),
|
|
Box::new(optimize_expr(rhs, state)),
|
|
pos
|
|
),
|
|
},
|
|
// lhs && rhs
|
|
Expr::And(lhs, rhs, pos) => match (*lhs, *rhs) {
|
|
// true && rhs -> rhs
|
|
(Expr::True(_), rhs) => {
|
|
state.set_dirty();
|
|
rhs
|
|
}
|
|
// false && rhs -> false
|
|
(Expr::False(pos), _) => {
|
|
state.set_dirty();
|
|
Expr::False(pos)
|
|
}
|
|
// lhs && true -> lhs
|
|
(lhs, Expr::True(_)) => {
|
|
state.set_dirty();
|
|
optimize_expr(lhs, state)
|
|
}
|
|
// lhs && rhs
|
|
(lhs, rhs) => Expr::And(
|
|
Box::new(optimize_expr(lhs, state)),
|
|
Box::new(optimize_expr(rhs, state)),
|
|
pos
|
|
),
|
|
},
|
|
// lhs || rhs
|
|
Expr::Or(lhs, rhs, pos) => match (*lhs, *rhs) {
|
|
// false || rhs -> rhs
|
|
(Expr::False(_), rhs) => {
|
|
state.set_dirty();
|
|
rhs
|
|
}
|
|
// true || rhs -> true
|
|
(Expr::True(pos), _) => {
|
|
state.set_dirty();
|
|
Expr::True(pos)
|
|
}
|
|
// lhs || false
|
|
(lhs, Expr::False(_)) => {
|
|
state.set_dirty();
|
|
optimize_expr(lhs, state)
|
|
}
|
|
// lhs || rhs
|
|
(lhs, rhs) => Expr::Or(Box::new(optimize_expr(lhs, state)), Box::new(optimize_expr(rhs, state)), pos),
|
|
},
|
|
|
|
// Do not call some special keywords
|
|
Expr::FnCall(id, None, args, def_value, pos) if DONT_EVAL_KEYWORDS.contains(&id.as_ref().as_ref())=>
|
|
Expr::FnCall(id, None, Box::new(args.into_iter().map(|a| optimize_expr(a, state)).collect()), def_value, pos),
|
|
|
|
// Eagerly call functions
|
|
Expr::FnCall(id, None, args, def_value, pos)
|
|
if state.optimization_level == OptimizationLevel::Full // full optimizations
|
|
&& args.iter().all(|expr| expr.is_constant()) // all arguments are constants
|
|
=> {
|
|
// First search in script-defined functions (can override built-in)
|
|
if state.fn_lib.iter().find(|(name, len)| name == id.as_ref() && *len == args.len()).is_some() {
|
|
// A script-defined function overrides the built-in function - do not make the call
|
|
return Expr::FnCall(id, None, Box::new(args.into_iter().map(|a| optimize_expr(a, state)).collect()), def_value, pos);
|
|
}
|
|
|
|
let mut arg_values: Vec<_> = args.iter().map(Expr::get_constant_value).collect();
|
|
let mut call_args: Vec<_> = arg_values.iter_mut().collect();
|
|
|
|
// Save the typename of the first argument if it is `type_of()`
|
|
// This is to avoid `call_args` being passed into the closure
|
|
let arg_for_type_of = if *id == KEYWORD_TYPE_OF && call_args.len() == 1 {
|
|
state.engine.map_type_name(call_args[0].type_name())
|
|
} else {
|
|
""
|
|
};
|
|
|
|
call_fn(&state.engine.packages, &state.engine.functions, &id, &mut call_args, pos).ok()
|
|
.and_then(|result|
|
|
result.or_else(|| {
|
|
if !arg_for_type_of.is_empty() {
|
|
// Handle `type_of()`
|
|
Some(arg_for_type_of.to_string().into())
|
|
} else {
|
|
// Otherwise use the default value, if any
|
|
def_value.clone().map(|v| *v)
|
|
}
|
|
}).and_then(|result| map_dynamic_to_expr(result, pos))
|
|
.map(|expr| {
|
|
state.set_dirty();
|
|
expr
|
|
})
|
|
).unwrap_or_else(||
|
|
// Optimize function call arguments
|
|
Expr::FnCall(id, None, Box::new(args.into_iter().map(|a| optimize_expr(a, state)).collect()), def_value, pos)
|
|
)
|
|
}
|
|
|
|
// id(args ..) -> optimize function call arguments
|
|
Expr::FnCall(id, modules, args, def_value, pos) =>
|
|
Expr::FnCall(id, modules, Box::new(args.into_iter().map(|a| optimize_expr(a, state)).collect()), def_value, pos),
|
|
|
|
// constant-name
|
|
Expr::Variable(name, None, _, pos) if state.contains_constant(&name) => {
|
|
state.set_dirty();
|
|
|
|
// Replace constant with value
|
|
state.find_constant(&name).expect("should find constant in scope!").clone().set_position(pos)
|
|
}
|
|
|
|
// All other expressions - skip
|
|
expr => expr,
|
|
}
|
|
}
|
|
|
|
fn optimize<'a>(
|
|
statements: Vec<Stmt>,
|
|
engine: &Engine,
|
|
scope: &Scope,
|
|
fn_lib: &'a [(&'a str, usize)],
|
|
level: OptimizationLevel,
|
|
) -> Vec<Stmt> {
|
|
// If optimization level is None then skip optimizing
|
|
if level == OptimizationLevel::None {
|
|
return statements;
|
|
}
|
|
|
|
// Set up the state
|
|
let mut state = State::new(engine, fn_lib, level);
|
|
|
|
// Add constants from the scope into the state
|
|
scope
|
|
.iter()
|
|
.filter(|ScopeEntry { typ, expr, .. }| {
|
|
// Get all the constants with definite constant expressions
|
|
*typ == ScopeEntryType::Constant
|
|
&& expr.as_ref().map(|v| v.is_constant()).unwrap_or(false)
|
|
})
|
|
.for_each(|ScopeEntry { name, expr, .. }| {
|
|
state.push_constant(
|
|
name.as_ref(),
|
|
(**expr.as_ref().expect("should be Some(expr)")).clone(),
|
|
)
|
|
});
|
|
|
|
let orig_constants_len = state.constants.len();
|
|
|
|
let mut result = statements;
|
|
|
|
// Optimization loop
|
|
loop {
|
|
state.reset();
|
|
state.restore_constants(orig_constants_len);
|
|
|
|
let num_statements = result.len();
|
|
|
|
result = result
|
|
.into_iter()
|
|
.enumerate()
|
|
.map(|(i, stmt)| {
|
|
match stmt {
|
|
Stmt::Const(ref name, ref value, _) => {
|
|
// Load constants
|
|
state.push_constant(name.as_ref(), value.as_ref().clone());
|
|
stmt // Keep it in the global scope
|
|
}
|
|
_ => {
|
|
// Keep all variable declarations at this level
|
|
// and always keep the last return value
|
|
let keep = match stmt {
|
|
Stmt::Let(_, _, _) | Stmt::Import(_, _, _) => true,
|
|
_ => i == num_statements - 1,
|
|
};
|
|
optimize_stmt(stmt, &mut state, keep)
|
|
}
|
|
}
|
|
})
|
|
.collect();
|
|
|
|
if !state.is_dirty() {
|
|
break;
|
|
}
|
|
}
|
|
|
|
// Eliminate code that is pure but always keep the last statement
|
|
let last_stmt = result.pop();
|
|
|
|
// Remove all pure statements at global level
|
|
result.retain(|stmt| !stmt.is_pure());
|
|
|
|
// Add back the last statement unless it is a lone No-op
|
|
if let Some(stmt) = last_stmt {
|
|
if !result.is_empty() || !matches!(stmt, Stmt::Noop(_)) {
|
|
result.push(stmt);
|
|
}
|
|
}
|
|
|
|
result
|
|
}
|
|
|
|
/// Optimize an AST.
|
|
pub fn optimize_into_ast(
|
|
engine: &Engine,
|
|
scope: &Scope,
|
|
statements: Vec<Stmt>,
|
|
functions: Vec<FnDef>,
|
|
level: OptimizationLevel,
|
|
) -> AST {
|
|
#[cfg(feature = "no_optimize")]
|
|
const level: OptimizationLevel = OptimizationLevel::None;
|
|
|
|
let fn_lib: Vec<_> = functions
|
|
.iter()
|
|
.map(|fn_def| (fn_def.name.as_str(), fn_def.params.len()))
|
|
.collect();
|
|
|
|
let lib = FunctionsLib::from_vec(
|
|
functions
|
|
.iter()
|
|
.cloned()
|
|
.map(|mut fn_def| {
|
|
if !level.is_none() {
|
|
let pos = fn_def.body.position();
|
|
|
|
// Optimize the function body
|
|
let mut body =
|
|
optimize(vec![*fn_def.body], engine, &Scope::new(), &fn_lib, level);
|
|
|
|
// {} -> Noop
|
|
fn_def.body = Box::new(match body.pop().unwrap_or_else(|| Stmt::Noop(pos)) {
|
|
// { return val; } -> val
|
|
Stmt::ReturnWithVal(Some(val), ReturnType::Return, _) => Stmt::Expr(val),
|
|
// { return; } -> ()
|
|
Stmt::ReturnWithVal(None, ReturnType::Return, pos) => {
|
|
Stmt::Expr(Box::new(Expr::Unit(pos)))
|
|
}
|
|
// All others
|
|
stmt => stmt,
|
|
});
|
|
}
|
|
fn_def
|
|
})
|
|
.collect(),
|
|
);
|
|
|
|
AST::new(
|
|
match level {
|
|
OptimizationLevel::None => statements,
|
|
OptimizationLevel::Simple | OptimizationLevel::Full => {
|
|
optimize(statements, engine, &scope, &fn_lib, level)
|
|
}
|
|
},
|
|
lib,
|
|
)
|
|
}
|