Avoid pulling in std for no-std.

Cargo.toml

@@ -46,6 +46,7 @@ codegen-units = 1
 
 [dependencies.libm]
 version = "0.2.1"
+default_features = false
 optional = true
 
 [dependencies.core-error]

src/packages/arithmetic.rs

@@ -7,6 +7,9 @@ use crate::token::Position;
 #[cfg(not(feature = "no_float"))]
 use crate::parser::FLOAT;
 
+#[cfg(not(feature = "no_float"))]
+use num_traits::*;
+
 use num_traits::{
     identities::Zero, CheckedAdd, CheckedDiv, CheckedMul, CheckedNeg, CheckedRem, CheckedShl,
     CheckedShr, CheckedSub,

src/packages/math_basic.rs

@@ -6,6 +6,9 @@ use crate::token::Position;
 #[cfg(not(feature = "no_float"))]
 use crate::parser::FLOAT;
 
+#[cfg(not(feature = "no_float"))]
+use num_traits::*;
+
 use crate::stdlib::{boxed::Box, format, i32, i64};
 
 #[cfg(feature = "only_i32")]

src/parser.rs

@@ -608,6 +608,7 @@ impl Hash for CustomExpr {
 #[derive(Debug, PartialEq, PartialOrd, Clone)]
 pub struct FloatWrapper(pub FLOAT, pub Position);
 
+#[cfg(not(feature = "no_float"))]
 impl Hash for FloatWrapper {
     fn hash<H: Hasher>(&self, state: &mut H) {
         state.write(&self.0.to_le_bytes());