public override bool NeedParens(OutputContext output)
{
var p = output.Parent();
// !(a = false) → true
if (p is AstUnary)
{
return(true);
}
// 1 + (a = 2) + 3 → 6, side effect setting a = 2
if (p is AstBinary && !(p is AstAssign))
{
return(true);
}
// (a = func)() —or— new (a = Object)()
if (p is AstCall call && call.Expression == this)
{
return(true);
}
// (a = foo) ? bar : baz
if (p is AstConditional conditional && conditional.Condition == this)
{
return(true);
}
// (a = foo)["prop"] —or— (a = foo).prop
if (p is AstPropAccess propAccess && propAccess.Expression == this)
{
return(true);
}
return(false);
}
protected void DoPrint(OutputContext output, string kind)
{
output.Print(kind);
output.Space();
for (var i = 0u; i < Definitions.Count; i++)
{
if (i > 0)
{
output.Comma();
}
Definitions[i].Print(output);
}
var p = output.Parent();
if (p is AstFor astFor && astFor.Init == this)
{
return;
}
if (p is AstForIn astForIn && astForIn.Init == this)
{
return;
}
if (p == null)
{
return;
}
output.Semicolon();
}
public override bool NeedParens(OutputContext output)
{
var p = output.Parent();
// (yield 1) + (yield 2)
// a = yield 3
if (p is AstBinary binary && binary.Operator != Operator.Assignment)
{
return(true);
}
// (yield 1)()
// new (yield 1)()
if (p is AstCall call && call.Expression == this)
{
return(true);
}
// (yield 1) ? yield 2 : yield 3
if (p is AstConditional conditional && conditional.Condition == this)
{
return(true);
}
// -(yield 4)
if (p is AstUnary)
{
return(true);
}
// (yield x).foo
// (yield x)['foo']
if (p is AstPropAccess propAccess && propAccess.Expression == this)
{
return(true);
}
return(false);
}
public override bool NeedParens(OutputContext output)
{
var p = output.Parent();
return(!output.NeedConstructorParens(this) &&
(p is AstPropAccess || // (new Date).getTime(), (new Date)["getTime"]()
p is AstCall call && call.Expression == this)); // (new foo)(bar)
}
public override bool NeedParens(OutputContext output)
{
var p = output.Parent();
return(p is AstPropAccess propAccess && propAccess.Expression == this ||
p is AstCall call && call.Expression == this ||
output.Options.Safari10 && p is AstUnaryPrefix);
}
public override bool NeedParens(OutputContext output)
{
var p = output.Parent();
if (p is AstNew aNew && aNew.Expression == this ||
p is AstExport {
IsDefault : true
} && Expression is AstFunction)
public override bool NeedParens(OutputContext output)
{
var p = output.Parent();
if (p is AstNew aNew && aNew.Expression == this ||
p is AstExport export && export.IsDefault && Expression is AstFunction)
{
return(true);
}
// workaround for Safari bug https://bugs.webkit.org/show_bug.cgi?id=123506
return(Expression is AstFunction &&
p is AstPropAccess propAccess &&
propAccess.Expression == this &&
output.Parent(1) is AstAssign assign &&
assign.Left == p);
}
public override bool NeedParens(OutputContext output)
{
var p = output.Parent();
return(p is AstPropAccess propAccess && propAccess.Expression == this ||
p is AstCall call && call.Expression == this ||
p is AstBinary binary &&
binary.Operator == Operator.Power &&
this is AstUnaryPrefix thisUnaryPrefix &&
binary.Left == this &&
thisUnaryPrefix.Operator != Operator.Increment &&
thisUnaryPrefix.Operator != Operator.Decrement);
}
public override void CodeGen(OutputContext output)
{
var isTagged = output.Parent() is AstPrefixedTemplateString;
output.Print("`");
for (var i = 0u; i < Segments.Count; i++)
{
if (!(Segments[i] is AstTemplateSegment seg))
{
output.Print("${");
Segments[i].Print(output);
output.Print("}");
}
public override void CodeGen(OutputContext output)
{
Name.Print(output);
if (Value != null)
{
output.Space();
output.Print("=");
output.Space();
var p = output.Parent(1);
var noin = p is AstFor || p is AstForIn;
output.ParenthesizeForNoin(Value, noin);
}
}
public override bool NeedParens(OutputContext output)
{
if (output.Options.ShortenBooleans)
{
var p = output.Parent();
return(p is AstPropAccess propAccess && propAccess.Expression == this ||
p is AstCall call && call.Expression == this ||
p is AstBinary binary &&
binary.Operator == Operator.Power &&
binary.Left == this);
}
return(false);
}
public override bool NeedParens(OutputContext output)
{
var p = output.Parent();
if (p is AstPropAccess propAccess && propAccess.Expression == this)
{
if (Value < 0)
{
return(true);
}
}
return(false);
}
public override bool NeedParens(OutputContext output)
{
if (output.FirstInStatement())
{
return(true);
}
if (output.Options.Webkit)
{
var p = output.Parent();
if (p is AstPropAccess propAccess && propAccess.Expression == this)
{
return(true);
}
}
if (output.Options.WrapIife)
{
var p = output.Parent();
return(p is AstCall call && call.Expression == this);
}
return(false);
}
public override void DoPrint(OutputContext output, bool nokeyword = false)
{
var parent = output.Parent();
var needsParens = parent is AstBinary ||
parent is AstUnary ||
(parent is AstCall call && this == call.Expression);
if (needsParens)
{
output.Print("(");
}
if (Async)
{
output.Print("async");
output.Space();
}
if (ArgNames.Count == 1 && ArgNames[0] is AstSymbol)
{
ArgNames[0].Print(output);
}
else
{
output.Print("(");
for (var i = 0u; i < ArgNames.Count; i++)
{
if (i > 0)
{
output.Comma();
}
ArgNames[i].Print(output);
}
output.Print(")");
}
output.Space();
output.Print("=>");
output.Space();
output.PrintBraced(Body, false);
if (needsParens)
{
output.Print(")");
}
}
public override bool NeedParens(OutputContext output)
{
var p = output.Parent();
if (p is AstNew aNew && aNew.Expression == this)
{
// i.e. new (foo.bar().baz)
//
// if there's one call into this subtree, then we need
// parens around it too, otherwise the call will be
// interpreted as passing the arguments to the upper New
// expression.
var walker = new WalkForParens();
walker.Walk(this);
return(walker.Parens);
}
return(false);
}
public override bool NeedParens(OutputContext output)
{
var p = output.Parent();
return(p is AstCall || // (foo, bar)() or foo(1, (2, 3), 4)
p is AstUnary || // !(foo, bar, baz)
p is AstBinary || // 1 + (2, 3) + 4 ==> 8
p is AstVarDef // var a = (1, 2), b = a + a; ==> b == 4
// (1, {foo:2}).foo or (1, {foo:2})["foo"] ==> 2
|| p is AstPropAccess propAccess && propAccess.Expression == this ||
p is AstArray || // [ 1, (2, 3), 4 ] ==> [ 1, 3, 4 ]
p is AstObjectProperty // { foo: (1, 2) }.foo ==> 2
// (false, true) ? (a = 10, b = 20) : (c = 30) ==> 20 (side effect, set a := 10 and b := 20)
|| p is AstConditional ||
p is AstArrow || // x => (x, x)
p is AstDefaultAssign || // x => (x = (0, function(){}))
p is AstExpansion || // [...(a, b)]
p is AstForOf forOf && this == forOf.Object || // for (e of (foo, bar)) {}
p is AstYield || // yield (foo, bar)
p is AstExport // export default (foo, bar)
);
}
public override void CodeGen(OutputContext output)
{
var isImport = output.Parent() is AstImport;
var definition = Name.Thedef;
var namesAreDifferent =
(definition?.MangledName ?? Name.Name) !=
ForeignName.Name;
if (namesAreDifferent)
{
if (isImport)
{
output.Print(ForeignName.Name);
}
else
{
Name.Print(output);
}
output.Space();
output.Print("as");
output.Space();
if (isImport)
{
Name.Print(output);
}
else
{
output.Print(ForeignName.Name);
}
}
else
{
Name.Print(output);
}
}
public override bool NeedParens(OutputContext output)
{
var p = output.Parent();
return(p is AstPropAccess propAccess && propAccess.Expression == this);
}