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expressionsem.d
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expressionsem.d
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/**
* Semantic analysis of expressions.
*
* Specification: ($LINK2 https://dlang.org/spec/expression.html, Expressions)
*
* Copyright: Copyright (C) 1999-2024 by The D Language Foundation, All Rights Reserved
* Authors: $(LINK2 https://www.digitalmars.com, Walter Bright)
* License: $(LINK2 https://www.boost.org/LICENSE_1_0.txt, Boost License 1.0)
* Source: $(LINK2 https://github.com/dlang/dmd/blob/master/src/dmd/expressionsem.d, _expressionsem.d)
* Documentation: https://dlang.org/phobos/dmd_expressionsem.html
* Coverage: https://codecov.io/gh/dlang/dmd/src/master/src/dmd/expressionsem.d
*/
module dmd.expressionsem;
import core.stdc.stdio;
import dmd.access;
import dmd.aggregate;
import dmd.aliasthis;
import dmd.arrayop;
import dmd.arraytypes;
import dmd.attrib;
import dmd.astcodegen;
import dmd.astenums;
import dmd.canthrow;
import dmd.chkformat;
import dmd.ctorflow;
import dmd.dscope;
import dmd.dsymbol;
import dmd.declaration;
import dmd.dclass;
import dmd.dcast;
import dmd.delegatize;
import dmd.denum;
import dmd.deps;
import dmd.dimport;
import dmd.dinterpret;
import dmd.dmangle;
import dmd.dmodule;
import dmd.dstruct;
import dmd.dsymbolsem;
import dmd.dtemplate;
import dmd.errors;
import dmd.errorsink;
import dmd.enumsem;
import dmd.escape;
import dmd.expression;
import dmd.file_manager;
import dmd.func;
import dmd.funcsem;
import dmd.globals;
import dmd.hdrgen;
import dmd.id;
import dmd.identifier;
import dmd.imphint;
import dmd.importc;
import dmd.init;
import dmd.initsem;
import dmd.inline;
import dmd.intrange;
import dmd.location;
import dmd.mtype;
import dmd.mustuse;
import dmd.nspace;
import dmd.objc;
import dmd.opover;
import dmd.optimize;
import dmd.parse;
import dmd.printast;
import dmd.postordervisitor;
import dmd.root.array;
import dmd.root.ctfloat;
import dmd.root.filename;
import dmd.common.outbuffer;
import dmd.rootobject;
import dmd.root.string;
import dmd.root.utf;
import dmd.semantic2;
import dmd.semantic3;
import dmd.sideeffect;
import dmd.safe;
import dmd.target;
import dmd.tokens;
import dmd.traits;
import dmd.typesem;
import dmd.typinf;
import dmd.utils;
import dmd.utils : arrayCastBigEndian;
import dmd.visitor;
enum LOGSEMANTIC = false;
/***********************************
* Determine if a `this` is needed to access `d`.
* Params:
* sc = context
* d = declaration to check
* Returns:
* true means a `this` is needed
*/
private bool isNeedThisScope(Scope* sc, Declaration d)
{
if (sc.intypeof == 1)
return false;
AggregateDeclaration ad = d.isThis();
if (!ad)
return false;
//printf("d = %s, ad = %s\n", d.toChars(), ad.toChars());
for (Dsymbol s = sc.parent; s; s = s.toParentLocal())
{
//printf("\ts = %s %s, toParent2() = %p\n", s.kind(), s.toChars(), s.toParent2());
if (AggregateDeclaration ad2 = s.isAggregateDeclaration())
{
if (ad2 == ad)
return false;
else if (ad2.isNested())
continue;
else
return true;
}
if (FuncDeclaration f = s.isFuncDeclaration())
{
if (f.isMemberLocal())
break;
}
}
return true;
}
/********************************************************
* Perform semantic analysis and CTFE on expressions to produce
* a string.
* Params:
* buf = append generated string to buffer
* sc = context
* exps = array of Expressions
* Returns:
* true on error
*/
bool expressionsToString(ref OutBuffer buf, Scope* sc, Expressions* exps)
{
if (!exps)
return false;
foreach (ex; *exps)
{
if (!ex)
continue;
auto sc2 = sc.startCTFE();
sc2.tinst = null;
sc2.minst = null; // prevents emission of any instantiated templates to object file
auto e2 = ex.expressionSemantic(sc2);
auto e3 = resolveProperties(sc2, e2);
sc2.endCTFE();
// allowed to contain types as well as expressions
auto e4 = ctfeInterpretForPragmaMsg(e3);
if (!e4 || e4.op == EXP.error)
return true;
// expand tuple
if (auto te = e4.isTupleExp())
{
if (expressionsToString(buf, sc, te.exps))
return true;
continue;
}
// char literals exp `.toStringExp` return `null` but we cant override it
// because in most contexts we don't want the conversion to succeed.
IntegerExp ie = e4.isIntegerExp();
const ty = (ie && ie.type) ? ie.type.ty : Terror;
if (ty.isSomeChar)
{
auto tsa = new TypeSArray(ie.type, IntegerExp.literal!1);
e4 = new ArrayLiteralExp(ex.loc, tsa, ie);
}
if (StringExp se = e4.toStringExp())
buf.writestring(se.toUTF8(sc).peekString());
else
buf.writestring(e4.toString());
}
return false;
}
/*****************************************
* Determine if `this` is available by walking up the enclosing
* scopes until a function is found.
*
* Params:
* sc = where to start looking for the enclosing function
* Returns:
* Found function if it satisfies `isThis()`, otherwise `null`
*/
FuncDeclaration hasThis(Scope* sc)
{
//printf("hasThis()\n");
Dsymbol p = sc.parent;
while (p && p.isTemplateMixin())
p = p.parent;
FuncDeclaration fdthis = p ? p.isFuncDeclaration() : null;
//printf("fdthis = %p, '%s'\n", fdthis, fdthis ? fdthis.toChars() : "");
// Go upwards until we find the enclosing member function
FuncDeclaration fd = fdthis;
while (1)
{
if (!fd)
{
return null;
}
if (!fd.isNested() || fd.isThis() || (fd.hasDualContext() && fd.isMember2()))
break;
Dsymbol parent = fd.parent;
while (1)
{
if (!parent)
return null;
TemplateInstance ti = parent.isTemplateInstance();
if (ti)
parent = ti.parent;
else
break;
}
fd = parent.isFuncDeclaration();
}
if (!fd.isThis() && !(fd.hasDualContext() && fd.isMember2()))
{
return null;
}
assert(fd.vthis);
return fd;
}
extern (D) bool findTempDecl(DotTemplateInstanceExp exp, Scope* sc)
{
auto ti = exp.ti;
auto e1 = exp.e1;
static if (LOGSEMANTIC)
{
printf("DotTemplateInstanceExp::findTempDecl('%s')\n", exp.toChars());
}
if (ti.tempdecl)
return true;
Expression e = new DotIdExp(exp.loc, e1, ti.name);
e = e.expressionSemantic(sc);
if (e.op == EXP.dot)
e = (cast(DotExp)e).e2;
Dsymbol s = null;
switch (e.op)
{
case EXP.overloadSet:
s = (cast(OverExp)e).vars;
break;
case EXP.dotTemplateDeclaration:
s = (cast(DotTemplateExp)e).td;
break;
case EXP.scope_:
s = (cast(ScopeExp)e).sds;
break;
case EXP.dotVariable:
s = (cast(DotVarExp)e).var;
break;
case EXP.variable:
s = (cast(VarExp)e).var;
break;
default:
return false;
}
return ti.updateTempDecl(sc, s);
}
/***********************************************************
* Resolve `exp` as a compile-time known string.
* Params:
* sc = scope
* exp = Expression which expected as a string
* s = What the string is expected for, will be used in error diagnostic.
* Returns:
* String literal, or `null` if error happens.
*/
StringExp semanticString(Scope *sc, Expression exp, const char* s)
{
sc = sc.startCTFE();
exp = exp.expressionSemantic(sc);
exp = resolveProperties(sc, exp);
sc = sc.endCTFE();
if (exp.op == EXP.error)
return null;
auto e = exp;
if (exp.type.isString())
{
e = e.ctfeInterpret();
if (e.op == EXP.error)
return null;
}
auto se = e.toStringExp();
if (!se)
{
error(exp.loc, "`string` expected for %s, not `(%s)` of type `%s`",
s, exp.toChars(), exp.type.toChars());
return null;
}
return se;
}
/****************************************
* Convert string to char[].
*/
StringExp toUTF8(StringExp se, Scope* sc)
{
if (se.sz != 1)
{
// Convert to UTF-8 string
se.committed = false;
Expression e = castTo(se, sc, Type.tchar.arrayOf());
e = e.optimize(WANTvalue);
auto result = e.isStringExp();
assert(result.sz == 1);
return result;
}
return se;
}
private Expression reorderSettingAAElem(BinExp exp, Scope* sc)
{
BinExp be = exp;
auto ie = be.e1.isIndexExp();
if (!ie)
return be;
if (ie.e1.type.toBasetype().ty != Taarray)
return be;
/* Fix evaluation order of setting AA element
* https://issues.dlang.org/show_bug.cgi?id=3825
* Rewrite:
* aa[k1][k2][k3] op= val;
* as:
* auto ref __aatmp = aa;
* auto ref __aakey3 = k1, __aakey2 = k2, __aakey1 = k3;
* auto ref __aaval = val;
* __aatmp[__aakey3][__aakey2][__aakey1] op= __aaval; // assignment
*/
Expression e0;
while (1)
{
Expression de;
ie.e2 = extractSideEffect(sc, "__aakey", de, ie.e2);
e0 = Expression.combine(de, e0);
auto ie1 = ie.e1.isIndexExp();
if (!ie1 ||
ie1.e1.type.toBasetype().ty != Taarray)
{
break;
}
ie = ie1;
}
assert(ie.e1.type.toBasetype().ty == Taarray);
Expression de;
ie.e1 = extractSideEffect(sc, "__aatmp", de, ie.e1);
e0 = Expression.combine(de, e0);
be.e2 = extractSideEffect(sc, "__aaval", e0, be.e2, true);
//printf("-e0 = %s, be = %s\n", e0.toChars(), be.toChars());
return Expression.combine(e0, be);
}
private Expression checkOpAssignTypes(BinExp binExp, Scope* sc)
{
auto e1 = binExp.e1;
auto e2 = binExp.e2;
auto op = binExp.op;
auto type = binExp.type;
auto loc = binExp.loc;
// At that point t1 and t2 are the merged types. type is the original type of the lhs.
Type t1 = e1.type;
Type t2 = e2.type;
// T opAssign floating yields a floating. Prevent truncating conversions (float to int).
// See https://issues.dlang.org/show_bug.cgi?id=3841.
// Should we also prevent double to float (type.isfloating() && type.size() < t2.size()) ?
if (op == EXP.addAssign || op == EXP.minAssign ||
op == EXP.mulAssign || op == EXP.divAssign || op == EXP.modAssign ||
op == EXP.powAssign)
{
if ((type.isintegral() && t2.isfloating()))
{
warning(loc, "`%s %s %s` is performing truncating conversion", type.toChars(), EXPtoString(op).ptr, t2.toChars());
}
}
// generate an error if this is a nonsensical *=,/=, or %=, eg real *= imaginary
if (op == EXP.mulAssign || op == EXP.divAssign || op == EXP.modAssign)
{
// Any multiplication by an imaginary or complex number yields a complex result.
// r *= c, i*=c, r*=i, i*=i are all forbidden operations.
const(char)* opstr = EXPtoString(op).ptr;
if (t1.isreal() && t2.iscomplex())
{
error(loc, "`%s %s %s` is undefined. Did you mean `%s %s %s.re`?", t1.toChars(), opstr, t2.toChars(), t1.toChars(), opstr, t2.toChars());
return ErrorExp.get();
}
else if (t1.isimaginary() && t2.iscomplex())
{
error(loc, "`%s %s %s` is undefined. Did you mean `%s %s %s.im`?", t1.toChars(), opstr, t2.toChars(), t1.toChars(), opstr, t2.toChars());
return ErrorExp.get();
}
else if ((t1.isreal() || t1.isimaginary()) && t2.isimaginary())
{
error(loc, "`%s %s %s` is an undefined operation", t1.toChars(), opstr, t2.toChars());
return ErrorExp.get();
}
}
// generate an error if this is a nonsensical += or -=, eg real += imaginary
if (op == EXP.addAssign || op == EXP.minAssign)
{
// Addition or subtraction of a real and an imaginary is a complex result.
// Thus, r+=i, r+=c, i+=r, i+=c are all forbidden operations.
if ((t1.isreal() && (t2.isimaginary() || t2.iscomplex())) || (t1.isimaginary() && (t2.isreal() || t2.iscomplex())))
{
error(loc, "`%s %s %s` is undefined (result is complex)", t1.toChars(), EXPtoString(op).ptr, t2.toChars());
return ErrorExp.get();
}
if (type.isreal() || type.isimaginary())
{
assert(global.errors || t2.isfloating());
e2 = e2.castTo(sc, t1);
}
}
if (op == EXP.mulAssign)
{
if (t2.isfloating())
{
if (t1.isreal())
{
if (t2.isimaginary() || t2.iscomplex())
{
e2 = e2.castTo(sc, t1);
}
}
else if (t1.isimaginary())
{
if (t2.isimaginary() || t2.iscomplex())
{
switch (t1.ty)
{
case Timaginary32:
t2 = Type.tfloat32;
break;
case Timaginary64:
t2 = Type.tfloat64;
break;
case Timaginary80:
t2 = Type.tfloat80;
break;
default:
assert(0);
}
e2 = e2.castTo(sc, t2);
}
}
}
}
else if (op == EXP.divAssign)
{
if (t2.isimaginary())
{
if (t1.isreal())
{
// x/iv = i(-x/v)
// Therefore, the result is 0
e2 = new CommaExp(loc, e2, new RealExp(loc, CTFloat.zero, t1));
e2.type = t1;
Expression e = new AssignExp(loc, e1, e2);
e.type = t1;
return e;
}
else if (t1.isimaginary())
{
Type t3;
switch (t1.ty)
{
case Timaginary32:
t3 = Type.tfloat32;
break;
case Timaginary64:
t3 = Type.tfloat64;
break;
case Timaginary80:
t3 = Type.tfloat80;
break;
default:
assert(0);
}
e2 = e2.castTo(sc, t3);
Expression e = new AssignExp(loc, e1, e2);
e.type = t1;
return e;
}
}
}
else if (op == EXP.modAssign)
{
if (t2.iscomplex())
{
error(loc, "cannot perform modulo complex arithmetic");
return ErrorExp.get();
}
}
return binExp;
}
private Expression extractOpDollarSideEffect(Scope* sc, UnaExp ue)
{
Expression e0;
Expression e1 = Expression.extractLast(ue.e1, e0);
// https://issues.dlang.org/show_bug.cgi?id=12585
// Extract the side effect part if ue.e1 is comma.
if (sc.ctfe ? hasSideEffect(e1) : !isTrivialExp(e1)) // match logic in extractSideEffect()
{
/* Even if opDollar is needed, 'e1' should be evaluate only once. So
* Rewrite:
* e1.opIndex( ... use of $ ... )
* e1.opSlice( ... use of $ ... )
* as:
* (ref __dop = e1, __dop).opIndex( ... __dop.opDollar ...)
* (ref __dop = e1, __dop).opSlice( ... __dop.opDollar ...)
*/
e1 = extractSideEffect(sc, "__dop", e0, e1, false);
assert(e1.isVarExp());
e1.isVarExp().var.storage_class |= STC.exptemp; // lifetime limited to expression
}
ue.e1 = e1;
return e0;
}
/****************************************
* Expand alias this tuples.
*/
TupleDeclaration isAliasThisTuple(Expression e)
{
if (!e.type)
return null;
Type t = e.type.toBasetype();
while (true)
{
if (Dsymbol s = t.toDsymbol(null))
{
if (auto ad = s.isAggregateDeclaration())
{
s = ad.aliasthis ? ad.aliasthis.sym : null;
if (s && s.isVarDeclaration())
{
TupleDeclaration td = s.isVarDeclaration().toAlias().isTupleDeclaration();
if (td && td.isexp)
return td;
}
if (Type att = t.aliasthisOf())
{
t = att;
continue;
}
}
}
return null;
}
}
/**************************************
* Runs semantic on ae.arguments. Declares temporary variables
* if '$' was used.
*/
Expression resolveOpDollar(Scope* sc, ArrayExp ae, Expression* pe0)
{
assert(!ae.lengthVar);
*pe0 = null;
AggregateDeclaration ad = isAggregate(ae.e1.type);
Dsymbol slice = search_function(ad, Id.slice);
//printf("slice = %s %s\n", slice.kind(), slice.toChars());
foreach (i, e; *ae.arguments)
{
if (i == 0)
*pe0 = extractOpDollarSideEffect(sc, ae);
if (e.op == EXP.interval && !(slice && slice.isTemplateDeclaration()))
{
Lfallback:
if (ae.arguments.length == 1)
return null;
error(ae.loc, "multi-dimensional slicing requires template `opSlice`");
return ErrorExp.get();
}
//printf("[%d] e = %s\n", i, e.toChars());
// Create scope for '$' variable for this dimension
auto sym = new ArrayScopeSymbol(sc, ae);
sym.parent = sc.scopesym;
sc = sc.push(sym);
ae.lengthVar = null; // Create it only if required
ae.currentDimension = i; // Dimension for $, if required
e = e.expressionSemantic(sc);
e = resolveProperties(sc, e);
if (ae.lengthVar && sc.func)
{
// If $ was used, declare it now
Expression de = new DeclarationExp(ae.loc, ae.lengthVar);
de = de.expressionSemantic(sc);
*pe0 = Expression.combine(*pe0, de);
}
sc = sc.pop();
if (auto ie = e.isIntervalExp())
{
auto tiargs = new Objects();
Expression edim = new IntegerExp(ae.loc, i, Type.tsize_t);
edim = edim.expressionSemantic(sc);
tiargs.push(edim);
auto fargs = new Expressions(2);
(*fargs)[0] = ie.lwr;
(*fargs)[1] = ie.upr;
uint xerrors = global.startGagging();
sc = sc.push();
FuncDeclaration fslice = resolveFuncCall(ae.loc, sc, slice, tiargs, ae.e1.type, ArgumentList(fargs), FuncResolveFlag.quiet);
sc = sc.pop();
global.endGagging(xerrors);
if (!fslice)
goto Lfallback;
e = new DotTemplateInstanceExp(ae.loc, ae.e1, slice.ident, tiargs);
e = new CallExp(ae.loc, e, fargs);
e = e.expressionSemantic(sc);
}
if (!e.type)
{
error(ae.loc, "`%s` has no value", e.toChars());
e = ErrorExp.get();
}
if (e.op == EXP.error)
return e;
(*ae.arguments)[i] = e;
}
return ae;
}
/**************************************
* Runs semantic on se.lwr and se.upr. Declares a temporary variable
* if '$' was used.
* Returns:
* ae, or ErrorExp if errors occurred
*/
Expression resolveOpDollar(Scope* sc, ArrayExp ae, IntervalExp ie, Expression* pe0)
{
//assert(!ae.lengthVar);
if (!ie)
return ae;
VarDeclaration lengthVar = ae.lengthVar;
bool errors = false;
// create scope for '$'
auto sym = new ArrayScopeSymbol(sc, ae);
sym.parent = sc.scopesym;
sc = sc.push(sym);
Expression sem(Expression e)
{
e = e.expressionSemantic(sc);
e = resolveProperties(sc, e);
if (!e.type)
{
error(ae.loc, "`%s` has no value", e.toChars());
errors = true;
}
return e;
}
ie.lwr = sem(ie.lwr);
ie.upr = sem(ie.upr);
if (ie.lwr.isErrorExp() || ie.upr.isErrorExp())
errors = true;
if (lengthVar != ae.lengthVar && sc.func)
{
// If $ was used, declare it now
Expression de = new DeclarationExp(ae.loc, ae.lengthVar);
de = de.expressionSemantic(sc);
*pe0 = Expression.combine(*pe0, de);
}
sc = sc.pop();
return errors ? ErrorExp.get() : ae;
}
/******************************
* Perform semantic() on an array of Expressions.
*/
extern(D) bool arrayExpressionSemantic(
Expression[] exps, Scope* sc, bool preserveErrors = false)
{
bool err = false;
foreach (ref e; exps)
{
if (e is null) continue;
auto e2 = e.expressionSemantic(sc);
if (e2.op == EXP.error)
err = true;
if (preserveErrors || e2.op != EXP.error)
e = e2;
}
return err;
}
/************************************************
* Handle the postblit call on lvalue, or the move of rvalue.
*
* Params:
* sc = the scope where the expression is encountered
* e = the expression the needs to be moved or copied (source)
* t = if the struct defines a copy constructor, the type of the destination
*
* Returns:
* The expression that copy constructs or moves the value.
*/
extern (D) Expression doCopyOrMove(Scope *sc, Expression e, Type t = null)
{
if (auto ce = e.isCondExp())
{
ce.e1 = doCopyOrMove(sc, ce.e1);
ce.e2 = doCopyOrMove(sc, ce.e2);
}
else
{
e = e.isLvalue() ? callCpCtor(sc, e, t) : valueNoDtor(e);
}
return e;
}
/*********************************************
* If e is an instance of a struct, and that struct has a copy constructor,
* rewrite e as:
* (tmp = e),tmp
* Input:
* sc = just used to specify the scope of created temporary variable
* destinationType = the type of the object on which the copy constructor is called;
* may be null if the struct defines a postblit
*/
private Expression callCpCtor(Scope* sc, Expression e, Type destinationType)
{
if (auto ts = e.type.baseElemOf().isTypeStruct())
{
StructDeclaration sd = ts.sym;
if (sd.postblit || sd.hasCopyCtor)
{
/* Create a variable tmp, and replace the argument e with:
* (tmp = e),tmp
* and let AssignExp() handle the construction.
* This is not the most efficient, ideally tmp would be constructed
* directly onto the stack.
*/
auto tmp = copyToTemp(STC.rvalue, "__copytmp", e);
if (sd.hasCopyCtor && destinationType)
{
// https://issues.dlang.org/show_bug.cgi?id=22619
// If the destination type is inout we can preserve it
// only if inside an inout function; if we are not inside
// an inout function, then we will preserve the type of
// the source
if (destinationType.hasWild && !(sc.func.storage_class & STC.wild))
tmp.type = e.type;
else
tmp.type = destinationType;
}
tmp.storage_class |= STC.nodtor;
tmp.dsymbolSemantic(sc);
Expression de = new DeclarationExp(e.loc, tmp);
Expression ve = new VarExp(e.loc, tmp);
de.type = Type.tvoid;
ve.type = e.type;
return Expression.combine(de, ve);
}
}
return e;
}
/************************************************
* If we want the value of this expression, but do not want to call
* the destructor on it.
*/
Expression valueNoDtor(Expression e)
{
auto ex = lastComma(e);
if (auto ce = ex.isCallExp())
{
/* The struct value returned from the function is transferred
* so do not call the destructor on it.
* Recognize:
* ((S _ctmp = S.init), _ctmp).this(...)
* and make sure the destructor is not called on _ctmp
* BUG: if ex is a CommaExp, we should go down the right side.
*/
if (auto dve = ce.e1.isDotVarExp())
{
if (dve.var.isCtorDeclaration())
{
// It's a constructor call
if (auto comma = dve.e1.isCommaExp())
{
if (auto ve = comma.e2.isVarExp())
{
VarDeclaration ctmp = ve.var.isVarDeclaration();
if (ctmp)
{
ctmp.storage_class |= STC.nodtor;
assert(!ce.isLvalue());
}
}
}
}
}
}
else if (auto ve = ex.isVarExp())
{
auto vtmp = ve.var.isVarDeclaration();
if (vtmp && (vtmp.storage_class & STC.rvalue))
{
vtmp.storage_class |= STC.nodtor;
}
}
return e;
}
/*
Checks if `exp` contains a direct access to a `noreturn`
variable. If that is the case, an `assert(0)` expression
is generated and returned. This function should be called
only after semantic analysis has been performed on `exp`.
Params:
exp = expression that is checked
Returns:
An `assert(0)` expression if `exp` contains a `noreturn`
variable access, `exp` otherwise.
*/
Expression checkNoreturnVarAccess(Expression exp)
{
assert(exp.type);
Expression result = exp;
if (exp.type.isTypeNoreturn() && !exp.isAssertExp() &&
!exp.isThrowExp() && !exp.isCallExp())
{
auto msg = new StringExp(exp.loc, "Accessed expression of type `noreturn`");
msg.type = Type.tstring;
result = new AssertExp(exp.loc, IntegerExp.literal!0, msg);
result.type = exp.type;
}
return result;
}
/******************************
* Find symbol in accordance with the UFCS name look up rule
*/
private Expression searchUFCS(Scope* sc, UnaExp ue, Identifier ident)
{
//printf("searchUFCS(ident = %s)\n", ident.toChars());
Loc loc = ue.loc;
// TODO: merge with Scope.search.searchScopes()
Dsymbol searchScopes(SearchOptFlags flags)
{
Dsymbol s = null;
for (Scope* scx = sc; scx; scx = scx.enclosing)
{
if (!scx.scopesym)
continue;
if (scx.scopesym.isModule())
flags |= SearchOpt.unqualifiedModule; // tell Module.search() that SearchOpt.localsOnly is to be obeyed
s = scx.scopesym.search(loc, ident, flags);
if (s)
{
// overload set contains only module scope symbols.
if (s.isOverloadSet())
break;
// selective/renamed imports also be picked up
if (AliasDeclaration ad = s.isAliasDeclaration())
{
if (ad._import)
break;
}
// See only module scope symbols for UFCS target.
Dsymbol p = s.toParent2();
if (p && p.isModule())
break;
}
s = null;
// Stop when we hit a module, but keep going if that is not just under the global scope
if (scx.scopesym.isModule() && !(scx.enclosing && !scx.enclosing.enclosing))
break;
}
return s;
}
SearchOptFlags flags = SearchOpt.all;
Dsymbol s;
if (sc.ignoresymbolvisibility)
flags |= SearchOpt.ignoreVisibility;
// First look in local scopes
s = searchScopes(flags | SearchOpt.localsOnly);
if (!s)
{
// Second look in imported modules
s = searchScopes(flags | SearchOpt.importsOnly);
}
if (!s)
return ue.e1.type.getProperty(sc, loc, ident, 0, ue.e1);
FuncDeclaration f = s.isFuncDeclaration();
if (f)
{
if (TemplateDeclaration td = getFuncTemplateDecl(f))
{
if (td.overroot)
td = td.overroot;
s = td;
}
}
if (auto dti = ue.isDotTemplateInstanceExp())
{
// https://issues.dlang.org/show_bug.cgi?id=23968
// Typically, deprecated alias declarations are caught
// when `TemplateInstance.findTempDecl` is called,
// however, in this case the tempdecl field is updated
// therefore `findTempDecl` will return immediately
// and not get the chance to issue the deprecation.
if (s.isAliasDeclaration())
s.checkDeprecated(ue.loc, sc);
auto ti = new TemplateInstance(loc, s.ident, dti.ti.tiargs);
if (!ti.updateTempDecl(sc, s))
return ErrorExp.get();
return new ScopeExp(loc, ti);
}
else
{
//printf("-searchUFCS() %s\n", s.toChars());
return new DsymbolExp(loc, s);
}
}
/******************************