refactor: remove unneeded index access

src/ast/bare-configure.ts

@@ -10,13 +10,14 @@ export function configure(schema: ast.Ast, config: Config): ast.Ast {
         aliasesInFlatUnion: new Set(),
         symbols: ast.symbols(schema),
     }
-    const defs = schema.defs.slice()
-    for (let i = 0; i < defs.length; i++) {
-        const type = configureType(c, defs[i].type, true)
-        if (defs[i].type !== type) {
-            const { alias, internal, comment, offset } = defs[i]
-            defs[i] = { alias, internal, type, comment, offset }
+    const defs: ast.AliasedType[] = []
+    for (let def of schema.defs) {
+        const type = configureType(c, def.type, true)
+        if (def.type !== type) {
+            const { alias, internal, comment, offset } = def
+            def = { alias, internal, type, comment, offset }
         }
+        defs.push(def)
     }
     for (let i = 0; i < defs.length; i++) {
         let type = defs[i].type

src/ast/bare-semantic-checker.ts

@@ -46,7 +46,7 @@ type Checker = {
 
 function checkTypeName(aliased: ast.AliasedType): void {
     const { alias, internal } = aliased
-    if (alias.length !== 0 && /^\d/.test(alias[0])) {
+    if (/^\d/.test(alias)) {
         if (!internal) {
             throw new CompilerError(
                 `the type name '${alias}' must not start with a figure or must be internal.`,
@@ -235,17 +235,16 @@ function checkNonVoid(c: Checker, type: ast.Type): void {
 }
 
 function checkUnionInvariants(c: Checker, type: ast.UnionType): void {
-    const tags = type.data
     // check type uniqueness
     const stringifiedTypes = new Set()
-    for (let i = 0; i < tags.length; i++) {
-        const stringifiedType = JSON.stringify(ast.withoutExtra(type.types[i]))
+    for (const ty of type.types) {
+        const stringifiedType = JSON.stringify(ast.withoutExtra(ty))
         // NOTE: this dirty check is ok because we initialize
         // every object in the same way (properties are in the same order)
         if (stringifiedTypes.has(stringifiedType)) {
             throw new CompilerError(
                 "a type cannot be repeated in an union.",
-                type.types[i].offset,
+                ty.offset,
             )
         }
         stringifiedTypes.add(stringifiedType)

src/parser/bare-lexer.ts

@@ -56,7 +56,7 @@ export function nextToken(lex: Lexer): void {
     offset += token.length
     token = ""
     while (offset < content.length) {
-        const c = content[offset]
+        const c = content[offset] as string
         if (c === "#") {
             // comment
             let index = content.indexOf("\n", offset + 1)