Fix no_std build.

src/fn_call.rs

@@ -1055,7 +1055,7 @@ impl Engine {
         } else {
             // If the first argument is a variable, and there is no curried arguments, convert to method-call style
             // in order to leverage potential &mut first argument and avoid cloning the value
-            if curry.is_empty() && args_expr[0].get_variable_access(false).is_some()  {
+            if curry.is_empty() && args_expr[0].get_variable_access(false).is_some() {
                 // func(x, ...) -> x.func(...)
                 arg_values = args_expr
                     .iter()

src/packages/iter_basic.rs

@@ -45,6 +45,8 @@ where
     Ok(StepRange::<T>(from, to, step))
 }
 
+#[cfg(not(feature = "only_i32"))]
+#[cfg(not(feature = "only_i64"))]
 macro_rules! reg_range {
     ($lib:expr, $x:expr, $( $y:ty ),*) => (
         $(
@@ -54,6 +56,8 @@ macro_rules! reg_range {
     )
 }
 
+#[cfg(not(feature = "only_i32"))]
+#[cfg(not(feature = "only_i64"))]
 macro_rules! reg_step {
     ($lib:expr, $x:expr, $( $y:ty ),*) => (
         $(

src/syntax.rs

@@ -10,7 +10,11 @@ use crate::token::{is_valid_identifier, Position, Token};
 use crate::utils::ImmutableString;
 use crate::StaticVec;
 
-use crate::stdlib::{boxed::Box, format, string::ToString};
+use crate::stdlib::{
+    boxed::Box,
+    format,
+    string::{String, ToString},
+};
 
 /// A general expression evaluation trait object.
 #[cfg(not(feature = "sync"))]