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dmd.clone
Define the implicit opEquals, opAssign, post blit, copy constructor and destructor for structs.
Authors:
License:
Source clone.d
Documentation https://dlang.org/phobos/dmd_clone.html
- pure StorageClass
mergeFuncAttrs
(StorageClasss1
, const FuncDeclarationf
); - Merge function attributes pure, nothrow, @safe, @nogc, and @disable from f into s1.Parameters:
StorageClass s1
storage class to merge into FuncDeclaration f
function Returns:merged storage class - FuncDeclaration
hasIdentityOpAssign
(AggregateDeclarationad
, Scope*sc
); - Check given aggregate actually has an identity opAssign or not.Parameters:
AggregateDeclaration ad
struct or class Scope* sc
current scope Returns:if found, returns FuncDeclaration of opAssign, otherwise null - FuncDeclaration
buildOpAssign
(StructDeclarationsd
, Scope*sc
); - Build opAssign for a struct.The generated opAssign function has the following signature:
ref S opAssign(S s) // S is the name of the `struct`
The opAssign function will be built for a struct S if the following constraints are met: 1. S does not have an identity opAssign defined. 2. S has at least one of the following members: a postblit (user-defined or generated for fields that have a defined postblit), a destructor (user-defined or generated for fields that have a defined destructor) or at least one field that has a defined opAssign. 3. S does not have any non-mutable fields. If S has a disabled destructor or at least one field that has a disabled opAssign, S.opAssign is going to be generated, but marked with @disable If S defines a destructor, the generated code for opAssign is:S __swap = void; __swap = this; // bit copy this = s; // bit copy __swap.dtor();
Otherwise, if S defines a postblit, the generated code for opAssign is:this = s;
Note that the parameter to the generated opAssign is passed by value, which means that the postblit is going to be called (if it is defined) in both of the above situations before entering the body of opAssign. The assignments in the above generated function bodies are blit expressions, so they can be regarded as memcpys (opAssign is not called as this will result in an infinite recursion; the postblit is not called because it has already been called when the parameter was passed by value). If S does not have a postblit or a destructor, but contains at least one field that defines an opAssign function (which is not disabled), then the body will make member-wise assignments:this.field1 = s.field1; this.field2 = s.field2; ...;
In this situation, the assignemnts are actual assign expressions (opAssign is used if defined).Parameters:StructDeclaration sd
struct to generate opAssign for Scope* sc
context Returns:generated opAssign function - bool
needOpEquals
(StructDeclarationsd
); - We need an opEquals for the struct if any fields has an opEquals. Generate one if a user-specified one does not exist.
- FuncDeclaration
buildOpEquals
(StructDeclarationsd
, Scope*sc
); - Build opEquals for struct. const bool opEquals(const S s) { ... }By fixing https://issues.dlang.org/show_bug.cgi?id=3789 opEquals is changed to be never implicitly generated. Now, struct objects comparison s1 == s2 is translated to: s1.tupleof == s2.tupleof to calculate structural equality. See EqualExp.op_overload.
- FuncDeclaration
buildXopEquals
(StructDeclarationsd
, Scope*sc
); - Build __xopEquals for TypeInfo_Struct static bool __xopEquals(ref const S p, ref const S q) { return p == q; }This is called by TypeInfo.equals(p1, p2). If the struct does not support const objects comparison, it will throw "not implemented" Error in runtime.
- FuncDeclaration
buildXopCmp
(StructDeclarationsd
, Scope*sc
); - Build __xopCmp for TypeInfo_Struct static bool __xopCmp(ref const S p, ref const S q) { return p.opCmp(q); }This is called by TypeInfo.compare(p1, p2). If the struct does not support const objects comparison, it will throw "not implemented" Error in runtime.
- FuncDeclaration
buildXtoHash
(StructDeclarationsd
, Scope*sc
); - Build _xtoHash for non-bitwise hashing static hash_t xtoHash(ref const S p) nothrow @trusted;
- DtorDeclaration
buildDtor
(AggregateDeclarationad
, Scope*sc
); - Create inclusive destructor for struct/class by aggregating all the destructors in dtors[] with the destructors for all the members.Parameters:
AggregateDeclaration ad
struct or class to build destructor for Scope* sc
context Returns:generated function, null if none neededNote Close similarity with StructDeclaration::buildPostBlit(), and the ordering changes (runs backward instead of forwards).
- DtorDeclaration
buildExternDDtor
(AggregateDeclarationad
, Scope*sc
); - build a shim function around the compound dtor that translates a C++ destructor to a destructor with extern(D) calling conventionParameters:
AggregateDeclaration ad
the aggregate that contains the destructor to wrap Scope* sc
the scope in which to analyze the new function Returns:the shim destructor, semantically analyzed and added to the class as a member - FuncDeclaration
buildInv
(AggregateDeclarationad
, Scope*sc
); - Create inclusive invariant for struct/class by aggregating all the invariants in invs[]. void __invariant() const [pure nothrow @trusted] { invs[0](), invs[1](), ...; }
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