/// <summary>
/// Creates a new declarative scope for use inside a function body.
/// </summary>
/// <param name="parentScope"> A reference to the parent scope. Can not be <c>null</c>. </param>
/// <param name="functionName"> The name of the function. Can be empty for an anonymous function. </param>
/// <param name="argumentNames"> The names of each of the function arguments. </param>
/// <returns> A new DeclarativeScope instance. </returns>
internal static DeclarativeScope CreateFunctionScope(Scope parentScope, string functionName, List <ArgVariable> args)
{
if (functionName == null)
{
throw new ArgumentNullException("functionName");
}
if (args == null)
{
throw new ArgumentNullException("args");
}
DeclarativeScope result = new DeclarativeScope(parentScope, 0);
if (string.IsNullOrEmpty(functionName) == false)
{
result.AddVariable(functionName);
}
// At this point, the 'this' keyword is already in args.
result.AddVariable("arguments");
foreach (ArgVariable arg in args)
{
result.Declare(arg);
arg.Scope = result;
}
return(result);
}
/// <summary>
/// Generates code to push the "this" value for a function call.
/// </summary>
/// <param name="generator"> The generator to output the CIL to. </param>
public void GenerateThis(ILGenerator generator)
{
// Optimization: if there are no with scopes, simply emit undefined.
bool scopeChainHasWithScope = false;
var scope = this.Scope;
do
{
if (scope is ObjectScope && ((ObjectScope)scope).ProvidesImplicitThisValue == true)
{
scopeChainHasWithScope = true;
break;
}
scope = scope.ParentScope;
} while (scope != null);
if (scopeChainHasWithScope == false)
{
// No with scopes in the scope chain, use undefined as the "this" value.
EmitHelpers.EmitUndefined(generator);
return;
}
scope = this.Scope;
do
{
DeclarativeScope dScope = scope as DeclarativeScope;
if (dScope != null)
{
if (dScope.HasDeclaredVariable(this.Name))
{
// The variable exists but declarative scopes always produce undefined for
// the "this" value.
EmitHelpers.EmitUndefined(generator);
break;
}
}
else
{
// Object scope - what object type is it for?
Prototype proto = (scope as ObjectScope).ScopePrototype;
_Variable = proto.GetProperty(Name);
if (_Variable != null)
{
// Output a get now:
_Variable.Get(generator);
break;
}
}
scope = scope.ParentScope;
} while (scope != null);
}
public override Statement ParseNoNewContext(Parser parser)
{
var result = new TryCatchFinallyStatement();
var labelled = parser.Labels(result);
// Consume the try keyword.
parser.Expect(KeywordToken.Try);
// Parse the try block.
result.TryBlock = parser.ParseBlock();
// The next token is either 'catch' or 'finally'.
if (parser.nextToken == KeywordToken.Catch)
{
// Consume the catch token.
parser.Expect(KeywordToken.Catch);
// Read the left parenthesis.
parser.Expect(PunctuatorToken.LeftParenthesis);
// Read the name of the variable to assign the exception to.
result.CatchVariableName = parser.ExpectIdentifier();
parser.ValidateVariableName(result.CatchVariableName);
// Read the right parenthesis.
parser.Expect(PunctuatorToken.RightParenthesis);
// Create a new scope for the catch variable.
result.CatchScope = DeclarativeScope.CreateCatchScope(parser.currentLetScope, result.CatchVariableName);
using (parser.CreateScopeContext(result.CatchScope, result.CatchScope))
{
// Parse the statements inside the catch block.
result.CatchBlock = parser.ParseBlock();
}
}
if (parser.nextToken == KeywordToken.Finally)
{
// Consume the finally token.
parser.Expect(KeywordToken.Finally);
// Read the finally statements.
result.FinallyBlock = parser.ParseBlock();
}
// There must be a catch or finally block.
if (result.CatchBlock == null && result.FinallyBlock == null)
{
throw new JavaScriptException(parser.engine, "SyntaxError", "Missing catch or finally after try", parser.LineNumber, parser.SourcePath);
}
return(labelled);
}
/// <summary>
/// Creates a new FunctionMethodGenerator instance.
/// </summary>
/// <param name="engine"> The script engine. </param>
/// <param name="scope"> The function scope. </param>
/// <param name="functionName"> The name of the function. </param>
/// <param name="includeNameInScope"> Indicates whether the name should be included in the function scope. </param>
/// <param name="args"> The names of the arguments. </param>
/// <param name="bodyText"> The source code of the function. </param>
/// <param name="body"> The root of the abstract syntax tree for the body of the function. </param>
/// <param name="scriptPath"> The URL or file system path that the script was sourced from. </param>
/// <param name="options"> Options that influence the compiler. </param>
public FunctionMethodGenerator(ScriptEngine engine, DeclarativeScope scope, string functionName, bool includeNameInScope, List <ArgVariable> args, Statement body, string scriptPath, CompilerOptions options)
: base(engine, scope, new DummyScriptSource(scriptPath), options)
{
this.Name = functionName;
this.IncludeNameInScope = includeNameInScope;
this.Arguments = args;
this.BodyRoot = body;
// Claim an ID:
MethodID = MethodLookup.GetNextID();
// Store the generated method in the cache:
MethodLookup.SaveAs(MethodID, this);
Validate();
}
/// <summary>
/// Creates a new declarative scope for use inside a catch statement.
/// </summary>
/// <param name="parentScope"> A reference to the parent scope. Can not be <c>null</c>. </param>
/// <param name="catchVariableName"> The name of the catch variable. </param>
/// <returns> A new DeclarativeScope instance. </returns>
internal static DeclarativeScope CreateCatchScope(Scope parentScope, string catchVariableName)
{
if (parentScope == null)
{
throw new ArgumentNullException("parentScope", "Catch scopes must have a parent scope.");
}
if (catchVariableName == null)
{
throw new ArgumentNullException("catchVariableName");
}
DeclarativeScope result = new DeclarativeScope(parentScope, 0);
result.AddVariable(catchVariableName);
result.CanDeclareVariables = false; // Only the catch variable can be declared in this scope.
return(result);
}
/// <summary>
/// Creates a new FunctionContext instance.
/// </summary>
/// <param name="engine"> The script engine. </param>
/// <param name="scope"> The function scope. </param>
/// <param name="functionName"> The name of the function. </param>
/// <param name="args"> The names of the arguments. </param>
/// <param name="body"> The source code for the body of the function. </param>
/// <param name="options"> Options that influence the compiler. </param>
public FunctionMethodGenerator(ScriptEngine engine, DeclarativeScope scope, string functionName, List <ArgVariable> args, string body, CompilerOptions options)
: base(engine, scope, new StringScriptSource(body), options)
{
this.Name = functionName;
this.Arguments = args;
}