Remove dependency on lazy_static

For a hashset of only 6 elements that is only checked once, there's not
really any point to pull in an extra dependency or use a hash set at
all.

crates/qasm2/Cargo.toml

@@ -13,5 +13,4 @@ crate-type = ["cdylib"]
 
 [dependencies]
 hashbrown = "0.13.2"
-lazy_static = "1.4"
 pyo3 = { version = "0.18.1", features = ["extension-module"] }

crates/qasm2/src/lib.rs

@@ -10,9 +10,6 @@
 // copyright notice, and modified files need to carry a notice indicating
 // that they have been altered from the originals.
 
-#[macro_use]
-extern crate lazy_static;
-
 use pyo3::prelude::*;
 use pyo3::Python;
 

crates/qasm2/src/parse.rs

@@ -56,18 +56,7 @@ const QELIB1: [(&str, usize, usize); 23] = [
     ("cu3", 3, 2),
 ];
 
-lazy_static! {
-    static ref BUILTIN_CLASSICAL: HashSet<&'static str> = {
-        let mut out = HashSet::with_capacity(6);
-        out.insert("cos");
-        out.insert("exp");
-        out.insert("ln");
-        out.insert("sin");
-        out.insert("sqrt");
-        out.insert("tan");
-        out
-    };
-}
+const BUILTIN_CLASSICAL: [&str; 6] = ["cos", "exp", "ln", "sin", "sqrt", "tan"];
 
 /// Define a simple newtype that just has a single non-public `usize` field, has a `new`
 /// constructor, and implements `Copy` and `IntoPy`.  The first argument is the name of the type,
@@ -316,7 +305,7 @@ impl State {
         state.define_gate(None, "U".to_owned(), 3, 1)?;
         state.define_gate(None, "CX".to_owned(), 0, 2)?;
         for classical in custom_classical {
-            if BUILTIN_CLASSICAL.contains(&*classical.name) {
+            if BUILTIN_CLASSICAL.contains(&&*classical.name) {
                 return Err(QASM2ParseError::new_err(message_generic(
                     None,
                     &format!(