Refactor to string interpolation where possible in compiler

src/builtins.ts

@@ -9956,7 +9956,7 @@ function ensureVisitMembersOf(compiler: Compiler, instance: Class): void {
   var base = instance.base;
   if (base) {
     body.push(
-      module.call(base.internalName + "~visit", [
+      module.call(`${base.internalName}~visit`, [
         module.local_get(0, sizeTypeRef), // this
         module.local_get(1, TypeRef.I32)  // cookie
       ], TypeRef.None)
@@ -10035,7 +10035,7 @@ function ensureVisitMembersOf(compiler: Compiler, instance: Class): void {
   }
 
   // Create the visitor function
-  instance.visitRef = module.addFunction(instance.internalName + "~visit",
+  instance.visitRef = module.addFunction(`${instance.internalName}~visit`,
     createType([sizeTypeRef, TypeRef.I32]),
     TypeRef.None,
     needsTempValue ? [ sizeTypeRef ] : null,
@@ -10073,7 +10073,7 @@ export function compileVisitMembers(compiler: Compiler): void {
       cases[i] = module.return();
     } else {
       cases[i] = module.block(null, [
-        module.call(instance.internalName + "~visit", [
+        module.call(`${instance.internalName}~visit`, [
           module.local_get(0, sizeTypeRef), // this
           module.local_get(1, TypeRef.I32)  // cookie
         ], TypeRef.None),
@@ -10252,7 +10252,13 @@ export function compileClassInstanceOf(compiler: Compiler, prototype: ClassProto
     )
   );
 
-  module.addFunction(prototype.internalName + "~instanceof", sizeTypeRef, TypeRef.I32, null, module.flatten(stmts));
+  module.addFunction(
+    `${prototype.internalName}~instanceof`,
+    sizeTypeRef,
+    TypeRef.I32,
+    null,
+    module.flatten(stmts)
+  );
 }
 
 // Helpers

src/compiler.ts

@@ -2341,11 +2341,11 @@ export class Compiler extends DiagnosticEmitter {
     var flowBefore = flow.fork();
     this.currentFlow = flow;
 
-    var breakLabel = "do-break|" + label;
+    var breakLabel = `do-break|${label}`;
     flow.breakLabel = breakLabel;
-    var continueLabel = "do-continue|" + label;
+    var continueLabel = `do-continue|${label}`;
     flow.continueLabel = continueLabel;
-    var loopLabel = "do-loop|" + label;
+    var loopLabel = `do-loop|${label}`;
 
     // Compile the body (always executes)
     var bodyFlow = flow.fork();
@@ -2487,11 +2487,11 @@ export class Compiler extends DiagnosticEmitter {
     var flow = outerFlow.fork(/* resetBreakContext */ true);
     this.currentFlow = flow;
 
-    var breakLabel = "for-break" + label;
+    var breakLabel = `for-break${label}`;
     flow.breakLabel = breakLabel;
-    var continueLabel = "for-continue|" + label;
+    var continueLabel = `for-continue|${label}`;
     flow.continueLabel = continueLabel;
-    var loopLabel = "for-loop|" + label;
+    var loopLabel = `for-loop|${label}`;
 
     // Compile initializer if present
     var initializer = statement.initializer;
@@ -2842,7 +2842,7 @@ export class Compiler extends DiagnosticEmitter {
       let case_ = cases[i];
       let label = case_.label;
       if (label) {
-        breaks[breakIndex++] = module.br("case" + i.toString() + "|" + context,
+        breaks[breakIndex++] = module.br(`case${i}|${context}`,
           module.binary(BinaryOp.EqI32,
             module.local_get(tempLocalIndex, TypeRef.I32),
             this.compileExpression(label, Type.u32,
@@ -2858,13 +2858,13 @@ export class Compiler extends DiagnosticEmitter {
     outerFlow.freeTempLocal(tempLocal);
 
     // otherwise br to default respectively out of the switch if there is no default case
-    breaks[breakIndex] = module.br((defaultIndex >= 0
-      ? "case" + defaultIndex.toString()
-      : "break"
-    ) + "|" + context);
+    breaks[breakIndex] = module.br(defaultIndex >= 0
+      ? `case${defaultIndex}|${context}`
+      : `break|${context}`
+    );
 
     // nest blocks in order
-    var currentBlock = module.block("case0|" + context, breaks, TypeRef.None);
+    var currentBlock = module.block(`case0|${context}`, breaks, TypeRef.None);
     var commonCategorical = FlowFlags.ANY_CATEGORICAL;
     var commonConditional = 0;
     for (let i = 0; i < numCases; ++i) {
@@ -2875,11 +2875,11 @@ export class Compiler extends DiagnosticEmitter {
       // Each switch case initiates a new branch
       let innerFlow = outerFlow.fork();
       this.currentFlow = innerFlow;
-      let breakLabel = "break|" + context;
+      let breakLabel = `break|${context}`;
       innerFlow.breakLabel = breakLabel;
 
       let isLast = i == numCases - 1;
-      let nextLabel = isLast ? breakLabel : "case" + (i + 1).toString() + "|" + context;
+      let nextLabel = isLast ? breakLabel : `case${i + 1}|${context}`;
       let stmts = new Array<ExpressionRef>(1 + numStatements);
       stmts[0] = currentBlock;
       let count = 1;
@@ -3194,9 +3194,9 @@ export class Compiler extends DiagnosticEmitter {
     var flowBefore = flow.fork();
     this.currentFlow = flow;
 
-    var breakLabel = "while-break|" + label;
+    var breakLabel = `while-break|${label}`;
     flow.breakLabel = breakLabel;
-    var continueLabel = "while-continue|" + label;
+    var continueLabel = `while-continue|${label}`;
     flow.continueLabel = continueLabel;
 
     // Precompute the condition
@@ -6812,10 +6812,9 @@ export class Compiler extends DiagnosticEmitter {
     // create a br_table switching over the number of optional parameters provided
     var numNames = numOptional + 1; // incl. outer block
     var names = new Array<string>(numNames);
-    var ofN = "of" + numOptional.toString();
+    var ofN = `of${numOptional}`;
     for (let i = 0; i < numNames; ++i) {
-      let label = i.toString() + ofN;
-      names[i] = label;
+      names[i] = `${i}${ofN}`;
     }
     var argumentsLength = this.ensureArgumentsLength();
     var table = module.block(names[0], [
@@ -7373,7 +7372,7 @@ export class Compiler extends DiagnosticEmitter {
     var isSemanticallyAnonymous = !isNamed || contextualType != Type.void;
     var prototype = new FunctionPrototype(
       isSemanticallyAnonymous
-        ? (isNamed ? declaration.name.text + "|" : "anonymous|") + (actualFunction.nextAnonymousId++).toString()
+        ? `${isNamed ? declaration.name.text : "anonymous"}|${actualFunction.nextAnonymousId++}`
         : declaration.name.text,
       actualFunction,
       declaration,
@@ -7974,7 +7973,7 @@ export class Compiler extends DiagnosticEmitter {
       // dynamic check against all possible concrete ids
       } else if (prototype.extends(classReference.prototype)) {
         this.pendingClassInstanceOf.add(prototype);
-        return module.call(prototype.internalName + "~instanceof", [ expr ], TypeRef.I32);
+        return module.call(`${prototype.internalName}~instanceof`, [ expr ], TypeRef.I32);
       }
     }
 

src/diagnostics.ts

@@ -142,33 +142,19 @@ export class DiagnosticMessage {
 
   /** Converts this message to a string. */
   toString(): string {
+    var category = diagnosticCategoryToString(this.category);
     var range = this.range;
+    var code = this.code;
+    var message = this.message;
     if (range) {
       let source = range.source;
-      return (
-        diagnosticCategoryToString(this.category) +
-        " " +
-        this.code.toString() +
-        ": \"" +
-        this.message +
-        "\" in " +
-        source.normalizedPath +
-        "(" +
-        source.lineAt(range.start).toString() +
-        "," +
-        source.columnAt().toString() +
-        "+" +
-        (range.end - range.start).toString() +
-        ")"
-      );
+      let path = source.normalizedPath;
+      let line = source.lineAt(range.start);
+      let column = source.columnAt();
+      let len = range.end - range.start;
+      return `${category} ${code}: "${message}" in ${path}(${line},${column}+${len})`;
     }
-    return (
-      diagnosticCategoryToString(this.category) +
-      " " +
-      this.code.toString() +
-      ": " +
-      this.message
-    );
+    return `${category} ${code}: ${message}`;
   }
 }
 

src/flow.ts

@@ -207,7 +207,7 @@ export class Flow {
   static createInline(parentFunction: Function, inlineFunction: Function): Flow {
     var flow = new Flow(parentFunction);
     flow.inlineFunction = inlineFunction;
-    flow.inlineReturnLabel = inlineFunction.internalName + "|inlined." + (inlineFunction.nextInlineId++).toString();
+    flow.inlineReturnLabel = `${inlineFunction.internalName}|inlined.${(inlineFunction.nextInlineId++)}`;
     if (inlineFunction.is(CommonFlags.CONSTRUCTOR)) {
       flow.initThisFieldFlags();
     }
@@ -1506,7 +1506,7 @@ export class Flow {
     if (this.is(FlowFlags.CONDITIONALLY_CONTINUES)) sb.push("CONDITIONALLY_CONTINUES");
     if (this.is(FlowFlags.CONDITIONALLY_ACCESSES_THIS)) sb.push("CONDITIONALLY_ACCESSES_THIS");
     if (this.is(FlowFlags.MAY_RETURN_NONTHIS)) sb.push("MAY_RETURN_NONTHIS");
-    return "Flow(" + this.actualFunction.toString() + ")[" + levels.toString() + "] " + sb.join(" ");
+    return `Flow(${this.actualFunction})[${levels}] ${sb.join(" ")}`;
   }
 }
 

src/module.ts

@@ -3028,7 +3028,7 @@ export class SwitchBuilder {
     var entry = new Array<ExpressionRef>(1 + numValues + 1);
     var labels = new Array<string>(numCases);
     for (let i = 0; i < numCases; ++i) {
-      labels[i] = "case" + i.toString() + labelPostfix;
+      labels[i] = `case${i}${labelPostfix}`;
     }
     entry[0] = module.local_set(localIndex, this.condition, false); // u32
     for (let i = 0; i < numValues; ++i) {
@@ -3041,7 +3041,7 @@ export class SwitchBuilder {
       );
     }
     var defaultIndex = this.defaultIndex;
-    var defaultLabel = "default" + labelPostfix;
+    var defaultLabel = `default${labelPostfix}`;
     entry[1 + numValues] = module.br(
       ~defaultIndex
         ? labels[defaultIndex]

src/program.ts

@@ -1543,8 +1543,8 @@ export class Program extends DiagnosticEmitter {
   /** Requires that a global library element of the specified kind is present and returns it. */
   private require(name: string, kind: ElementKind): Element {
     var element = this.lookup(name);
-    if (!element) throw new Error("Missing standard library component: " + name);
-    if (element.kind != kind) throw Error("Invalid standard library component kind: " + name);
+    if (!element) throw new Error(`Missing standard library component: ${name}`);
+    if (element.kind != kind) throw Error(`Invalid standard library component kind: ${name}`);
     return element;
   }
 
@@ -1557,15 +1557,15 @@ export class Program extends DiagnosticEmitter {
   requireClass(name: string): Class {
     var prototype = this.require(name, ElementKind.CLASS_PROTOTYPE);
     var resolved = this.resolver.resolveClass(<ClassPrototype>prototype, null);
-    if (!resolved) throw new Error("Invalid standard library class: " + name);
+    if (!resolved) throw new Error(`Invalid standard library class: ${name}`);
     return resolved;
   }
 
   /** Requires that a global function is present and returns it. */
   requireFunction(name: string, typeArguments: Type[] | null = null): Function {
     var prototype = <FunctionPrototype>this.require(name, ElementKind.FUNCTION_PROTOTYPE);
     var resolved = this.resolver.resolveFunction(prototype, typeArguments);
-    if (!resolved) throw new Error("Invalid standard library function: " + name);
+    if (!resolved) throw new Error(`Invalid standard library function: ${name}`);
     return resolved;
   }
 
@@ -2873,7 +2873,7 @@ export abstract class Element {
 
   /** Returns a string representation of this element. */
   toString(): string {
-    return this.internalName + ", kind=" + this.kind.toString();
+    return `${this.internalName}, kind=${this.kind}`;
   }
 }
 
@@ -3049,7 +3049,7 @@ export class File extends Element {
     assert(!program.filesByName.has(this.internalName));
     program.filesByName.set(this.internalName, this);
     var startFunction = this.program.makeNativeFunction(
-      "start:" + this.internalName,
+      `start:${this.internalName}`,
       new Signature(program, null, Type.void),
       this
     );
@@ -3693,9 +3693,7 @@ export class Function extends TypedElement {
     // if it has a name, check previously as this method will throw otherwise
     var localIndex = this.signature.parameterTypes.length + this.additionalLocals.length;
     if (this.is(CommonFlags.INSTANCE)) ++localIndex;
-    var localName = name != null
-      ? name
-      : "var$" + localIndex.toString();
+    var localName = name != null ? name : `var$${localIndex}`;
     if (!declaration) declaration = this.program.makeNativeVariableDeclaration(localName);
     var local = new Local(
       localName,
@@ -3851,31 +3849,39 @@ export class Field extends VariableLikeElement {
   /** Gets the internal name of the respective getter function. */
   get internalGetterName(): string {
     var cached = this._internalGetterName;
-    if (cached == null) this._internalGetterName = cached = this.parent.internalName + INSTANCE_DELIMITER + GETTER_PREFIX + this.name;
+    if (cached == null) {
+      this._internalGetterName = cached = `${this.parent.internalName}${INSTANCE_DELIMITER}${GETTER_PREFIX}${this.name}`;
+    }
     return cached;
   }
   private _internalGetterName: string | null = null;
 
   /** Gets the internal name of the respective setter function. */
   get internalSetterName(): string {
     var cached = this._internalSetterName;
-    if (cached == null) this._internalSetterName = cached = this.parent.internalName + INSTANCE_DELIMITER + SETTER_PREFIX + this.name;
+    if (cached == null) {
+      this._internalSetterName = cached = `${this.parent.internalName}${INSTANCE_DELIMITER}${SETTER_PREFIX}${this.name}`;
+    }
     return cached;
   }
   private _internalSetterName: string | null = null;
 
   /** Gets the signature of the respective getter function. */
   get internalGetterSignature(): Signature {
     var cached = this._internalGetterSignature;
-    if (!cached) this._internalGetterSignature = cached = new Signature(this.program, null, this.type, this.thisType);
+    if (!cached) {
+      this._internalGetterSignature = cached = new Signature(this.program, null, this.type, this.thisType);
+    }
     return cached;
   }
   private _internalGetterSignature: Signature | null = null;
 
   /** Gets the signature of the respective setter function. */
   get internalSetterSignature(): Signature {
     var cached = this._internalSetterSignature;
-    if (!cached) this._internalGetterSignature = cached = new Signature(this.program, [ this.type ], Type.void, this.thisType);
+    if (!cached) {
+      this._internalGetterSignature = cached = new Signature(this.program, [ this.type ], Type.void, this.thisType);
+    }
     return cached;
   }
   private _internalSetterSignature: Signature | null = null;
@@ -4720,7 +4726,12 @@ function copyMembers(src: Element, dest: Element): void {
 }
 
 /** Mangles the internal name of an element with the specified name that is a child of the given parent. */
-export function mangleInternalName(name: string, parent: Element, isInstance: bool, asGlobal: bool = false): string {
+export function mangleInternalName(
+  name: string,
+  parent: Element,
+  isInstance: bool,
+  asGlobal: bool = false
+): string {
   switch (parent.kind) {
     case ElementKind.FILE: {
       if (asGlobal) return name;
@@ -4737,8 +4748,10 @@ export function mangleInternalName(name: string, parent: Element, isInstance: bo
       // fall-through
     }
     default: {
-      return mangleInternalName(parent.name, parent.parent, parent.is(CommonFlags.INSTANCE), asGlobal)
-           + (isInstance ? INSTANCE_DELIMITER : STATIC_DELIMITER) + name;
+      return (
+        mangleInternalName(parent.name, parent.parent, parent.is(CommonFlags.INSTANCE), asGlobal) +
+        (isInstance ? INSTANCE_DELIMITER : STATIC_DELIMITER) + name
+      );
     }
   }
 }
@@ -4749,7 +4762,7 @@ var cachedDefaultParameterNames: string[] = [];
 /** Gets the cached default parameter name for the specified index. */
 export function getDefaultParameterName(index: i32): string {
   for (let i = cachedDefaultParameterNames.length; i <= index; ++i) {
-    cachedDefaultParameterNames.push("$" + i.toString());
+    cachedDefaultParameterNames.push(`$${i}`);
   }
   return cachedDefaultParameterNames[index];
 }