dmd.expression

Defines the bulk of the classes which represent the AST at the expression level.

Specification: ($LINK2 https://dlang.org/spec/expression.html, Expressions)

Authors

Walter Bright

License

Boost License 1.0

Source: expression.d

Documentation: https://dlang.org/phobos/dmd_expression.html

Coverage: https://codecov.io/gh/dlang/dmd/src/master/src/dmd/expression.d

  • Modifiable

    Declaration

    enum Modifiable: int;

    Return value for checkModifiable

    • no

      Declaration

      no

      Not modifiable

    • yes

      Declaration

      yes

      Modifiable (the type is mutable)

    • initialization

      Declaration

      initialization

      Modifiable because it is initialization

  • ModifyFlags

    Declaration

    enum ModifyFlags: int;

    Specifies how the checkModify deals with certain situations

    • none

      Declaration

      none

      Issue error messages on invalid modifications of the variable

    • noError

      Declaration

      noError

      No errors are emitted for invalid modifications

    • fieldAssign

      Declaration

      fieldAssign

      The modification occurs for a subfield of the current variable

  • lastComma

    Declaration

    inout(Expression) lastComma(inout Expression e);

    Find the last non-comma expression.

    Parameters

    Expression e

    Expressions connected by commas

    Return Value

    right-most non-comma expression

  • isNeedThisScope

    Declaration

    bool isNeedThisScope(Scope* sc, Declaration d);

    Determine if a this is needed to access d.

    Parameters

    Scope* sc

    context

    Declaration d

    declaration to check

    Return Value

    true means a this is needed

  • expandTuples

    Declaration

    void expandTuples(Expressions* exps, Identifiers* names = null);

    Expand tuples in-place.

    Example: When there's a call f(10, pair: AliasSeq!(20, 30), single: 40), the input is: exps = [10, (20, 30), 40] names = [null, "pair", "single"] The arrays will be modified to: exps = [10, 20, 30, 40] names = [null, "pair", null, "single"]

    Parameters

    Expressions* exps

    array of Expressions

    Identifiers* names

    optional array of names corresponding to Expressions

  • isAliasThisTuple

    Declaration

    TupleDeclaration isAliasThisTuple(Expression e);

    Expand alias this tuples.

  • getFuncTemplateDecl

    Declaration

    @safe TemplateDeclaration getFuncTemplateDecl(Dsymbol s);

    If s is a function template, i.e. the only member of a template and that member is a function, return that template.

    Parameters

    Dsymbol s

    symbol that might be a function template

    Return Value

    template for that function, otherwise null

  • UnionExp

    Declaration

    struct UnionExp;

  • typeDotIdExp

    Declaration

    @safe DotIdExp typeDotIdExp(const ref Loc loc, Type type, Identifier ident);

    TypeDotIdExp

  • expToVariable

    Declaration

    VarDeclaration expToVariable(Expression e);

    Given an Expression, find the variable it really is.

    Discussion

    For example, a[index] is really a, and s.f is really s.

    Parameters

    Expression e

    Expression to look at

    Return Value

    variable if there is one, null if not

  • Expression

    Declaration

    abstract class Expression: dmd.ast_node.ASTNode;

    https://dlang.org/spec/expression.html#expression

    • size

      Declaration

      final const pure nothrow @nogc @safe size_t size();

      Return Value

      class instance size of this expression (implemented manually because extern(C++))

    • deinitialize

      Declaration

      static void deinitialize();

      Deinitializes the global state of the compiler.

      Discussion

      This can be used to restore the state set by _init to its original state.

    • copy

      Declaration

      final Expression copy();

      Does not do a deep copy.

    • combine

      Declaration

      static @safe Expression combine(Expression e1, Expression e2);

      Combine e1 and e2 by CommaExp if both are not NULL.

    • extractLast

      Declaration

      static @safe Expression extractLast(Expression e, out Expression e0);

      If 'e' is a tree of commas, returns the rightmost expression by stripping off it from the tree. The remained part of the tree is returned via e0. Otherwise 'e' is directly returned and e0 is set to NULL.

    • isLvalue

      Declaration

      bool isLvalue();

      Return !=0 if expression is an lvalue.

    • toLvalue

      Declaration

      Expression toLvalue(Scope* sc, Expression e);

      Give error if we're not an lvalue. If we can, convert expression to be an lvalue.

    • resolveLoc

      Declaration

      Expression resolveLoc(const ref Loc loc, Scope* sc);

      Resolve __FILE__, __LINE__, __MODULE__, __FUNCTION__, __PRETTY_FUNCTION__, _FILE_FULL_PATH__ to loc.

    • checkType

      Declaration

      bool checkType();

      Check that the expression has a valid type. If not, generates an error "... has no type".

      Return Value

      true if the expression is not valid.

      Note: When this function returns true, checkValue() should also return true.

    • checkValue

      Declaration

      bool checkValue();

      Check that the expression has a valid value. If not, generates an error "... has no value".

      Return Value

      true if the expression is not valid or has void type.

    • checkPurity

      Declaration

      final bool checkPurity(Scope* sc, FuncDeclaration f);

      Calling function f. Check the purity, i.e. if we're in a pure function we can only call other pure functions. Returns true if error occurs.

    • checkOverriddenDtor

      Declaration

      final void checkOverriddenDtor(Scope* sc, FuncDeclaration f, scope bool function(DtorDeclaration) check, const string checkName);

      Checks whether f is a generated DtorDeclaration that hides a user-defined one which passes check while f doesn't (e.g. when the user defined dtor is pure but the generated dtor is not). In that case the method will identify and print all members causing the attribute missmatch.

      Parameters

      Scope* sc

      scope

      FuncDeclaration f

      potential DtorDeclaration

      bool function(DtorDeclaration) check

      current check (e.g. whether it's pure)

      string checkName

      the kind of check (e.g. "pure")

    • checkPurity

      Declaration

      final bool checkPurity(Scope* sc, VarDeclaration v);

      Accessing variable v. Check for purity and safety violations. Returns true if error occurs.

    • checkSafety

      Declaration

      final bool checkSafety(Scope* sc, FuncDeclaration f);

      Calling function f. Check the safety, i.e. if we're in a @safe function we can only call @safe or @trusted functions. Returns true if error occurs.

    • checkNogc

      Declaration

      final bool checkNogc(Scope* sc, FuncDeclaration f);

      Calling function f. Check the @nogc-ness, i.e. if we're in a @nogc function we can only call other @nogc functions. Returns true if error occurs.

    • checkPostblit

      Declaration

      final bool checkPostblit(Scope* sc, Type t);

      Check that the postblit is callable if t is an array of structs. Returns true if error happens.

    • checkReadModifyWrite

      Declaration

      final bool checkReadModifyWrite(EXP rmwOp, Expression ex = null);

      Check whether the expression allows RMW operations, error with rmw operator diagnostic if not. ex is the RHS expression, or NULL if ++/-- is used (for diagnostics) Returns true if error occurs.

    • addressOf

      Declaration

      final Expression addressOf();

      Take address of expression.

    • deref

      Declaration

      final Expression deref();

      If this is a reference, dereference it.

    • isIdentical

      Declaration

      const bool isIdentical(const Expression e);

      Identical, not just equal. I.e. NaNs with different bit patterns are not identical

    • toBool

      Declaration

      Optional!bool toBool();

      Statically evaluate this expression to a bool if possible

      Return Value

      an optional thath either contains the value or is empty

  • IntegerExp

    Declaration

    class IntegerExp: dmd.expression.Expression;

    A compile-time known integer value

    • literal

      Declaration

      IntegerExp literal(int v)();

      Use this instead of creating new instances for commonly used literals such as 0 or 1.

      Parameters: v = The value of the expression

      Return Value

      A static instance of the expression, typed as Tint32.

    • createBool

      Declaration

      static IntegerExp createBool(bool b);

      Use this instead of creating new instances for commonly used bools.

      Parameters: b = The value of the expression

      Return Value

      A static instance of the expression, typed as Type.tbool.

  • ErrorExp

    Declaration

    class ErrorExp: dmd.expression.Expression;

    Use this expression for error recovery.

    Discussion

    It should behave as a 'sink' to prevent further cascaded error messages.

  • VoidInitExp

    Declaration

    class VoidInitExp: dmd.expression.Expression;

    An uninitialized value, generated from void initializers.

    Discussion

    https://dlang.org/spec/declaration.html#void_init

    • var

      Declaration

      VarDeclaration var;

      the variable from where the void value came from, null if not known

    • this

      Declaration

      @safe this(VarDeclaration var);

      Useful for error messages

  • RealExp

    Declaration

    class RealExp: dmd.expression.Expression;

    A compile-time known floating point number

  • ComplexExp

    Declaration

    class ComplexExp: dmd.expression.Expression;

    A compile-time complex number (deprecated)

  • IdentifierExp

    Declaration

    class IdentifierExp: dmd.expression.Expression;

    An identifier in the context of an expression (as opposed to a declaration)

    Discussion

    1. int x; // VarDeclaration with Identifier x++; // PostExp with IdentifierExp

  • DollarExp

    Declaration

    class DollarExp: dmd.expression.IdentifierExp;

    The dollar operator used when indexing or slicing an array. E.g a[$], a[1 .. $] etc.

    Discussion

    https://dlang.org/spec/arrays.html#array-length

  • DsymbolExp

    Declaration

    class DsymbolExp: dmd.expression.Expression;

    Won't be generated by parser.

  • ThisExp

    Declaration

    class ThisExp: dmd.expression.Expression;

    https://dlang.org/spec/expression.html#this

  • SuperExp

    Declaration

    class SuperExp: dmd.expression.ThisExp;

    https://dlang.org/spec/expression.html#super

  • NullExp

    Declaration

    class NullExp: dmd.expression.Expression;

    A compile-time known null value

    Discussion

    https://dlang.org/spec/expression.html#null

  • StringExp

    Declaration

    class StringExp: dmd.expression.Expression;

    https://dlang.org/spec/expression.html#string_literals

    • committed

      Declaration

      bool committed;

      Whether the string literal's type is fixed

      Example:

      1. wstring x = "abc"; // OK, string literal is flexible wstring y = cast(string) "abc"; // Error: type was committed after cast

    • hexString

      Declaration

      bool hexString;

      If the string is parsed from a hex string literal

    • numberOfCodeUnits

      Declaration

      const size_t numberOfCodeUnits(int tynto = 0);

      Return the number of code units the string would be if it were re-encoded as tynto.

      Parameters

      int tynto

      code unit type of the target encoding

      Return Value

      number of code units

    • writeTo

      Declaration

      const void writeTo(void* dest, bool zero, int tyto = 0);

      Write the contents of the string to dest. Use numberOfCodeUnits() to determine size of result.

      Parameters

      void* dest

      destination

      int tyto

      encoding type of the result

      bool zero

      add terminating 0

    • getCodeUnit

      Declaration

      const pure dchar getCodeUnit(size_t i);

      Get the code unit at index i

      Parameters

      size_t i

      index

      Return Value

      code unit at index i

    • setCodeUnit

      Declaration

      void setCodeUnit(size_t i, dchar c);

      Set the code unit at index i to c

      Parameters

      size_t i

      index

      dchar c

      code unit to set it to

    • compare

      Declaration

      const pure nothrow @nogc int compare(const StringExp se2);

      Compare two StringExp by length, then value

      Discussion

      The comparison is not the usual C-style comparison as seen with strcmp or memcmp, but instead first compare based on the length. This allows both faster lookup and sorting when comparing sparse data.

      This ordering scheme is relied on by the string-switching feature. Code in Druntime's core.internal.switch_ relies on this ordering when doing a binary search among case statements.

      Both StringExp should be of the same encoding.

      Parameters

      StringExp se2

      String expression to compare this to

      Return Value

      0 when this is equal to se2, a value greater than 0 if this should be considered greater than se2, and a value less than 0 if this is lesser than se2.

    • toStringz

      Declaration

      const const(char)[] toStringz();

      Convert string contents to a 0 terminated string, allocated by mem.xmalloc().

    • peekData

      Declaration

      const const(ubyte)[] peekData();

      Get a slice of the data.

    • borrowData

      Declaration

      ubyte[] borrowData();

      Borrow a slice of the data, so the caller can modify it in-place (!)

    • setData

      Declaration

      void setData(void* s, size_t len, ubyte sz);

      Set new string data. this becomes the new owner of the data.

  • TupleExp

    Declaration

    class TupleExp: dmd.expression.Expression;

    A sequence of expressions

    Discussion

    1. alias AliasSeq(T...) = T; alias Tup = AliasSeq!(3, int, "abc");

  • ArrayLiteralExp

    Declaration

    class ArrayLiteralExp: dmd.expression.Expression;

    [ e1, e2, e3, ... ]

    Discussion

    https://dlang.org/spec/expression.html#array_literals

    • basis

      Declaration

      Expression basis;

      If !is null, elements[] can be sparse and basis is used for the "default" element value. In other words, non-null elements[i] overrides this 'basis' value.

  • AssocArrayLiteralExp

    Declaration

    class AssocArrayLiteralExp: dmd.expression.Expression;

    [ key0 : value0, key1 : value1, ... ]

    Discussion

    https://dlang.org/spec/expression.html#associative_array_literals

    • lowering

      Declaration

      Expression lowering;

      Lower to core.internal.newaa for static initializaton

  • stageScrub

    Declaration

    enum int stageScrub;

    scrubReturnValue is running

  • stageSearchPointers

    Declaration

    enum int stageSearchPointers;

    hasNonConstPointers is running

  • stageOptimize

    Declaration

    enum int stageOptimize;

    optimize is running

  • stageApply

    Declaration

    enum int stageApply;

    apply is running

  • stageInlineScan

    Declaration

    enum int stageInlineScan;

    inlineScan is running

  • stageToCBuffer

    Declaration

    enum int stageToCBuffer;

    toCBuffer is running

  • StructLiteralExp

    Declaration

    class StructLiteralExp: dmd.expression.Expression;

    sd( e1, e2, e3, ... )

    • sd

      Declaration

      StructDeclaration sd;

      which aggregate this is for

    • elements

      Declaration

      Expressions* elements;

      parallels sd.fields[] with null entries for fields to skip

    • stype

      Declaration

      Type stype;

      final type of result (can be different from sd's type)

    • sym

      Declaration

      Symbol* sym;

      back end symbol to initialize with literal

    • inlinecopy

      Declaration

      StructLiteralExp inlinecopy;

      those fields need to prevent a infinite recursion when one field of struct initialized with 'this' pointer.

    • origin

      Declaration

      StructLiteralExp origin;

      pointer to the origin instance of the expression. once a new expression is created, origin is set to 'this'. anytime when an expression copy is created, 'origin' pointer is set to 'origin' pointer value of the original expression.

    • stageflags

      Declaration

      ubyte stageflags;

      anytime when recursive function is calling, 'stageflags' marks with bit flag of current stage and unmarks before return from this function. 'inlinecopy' uses similar 'stageflags' and from multiple evaluation 'doInline' (with infinite recursion) of this expression.

    • useStaticInit

      Declaration

      bool useStaticInit;

      if this is true, use the StructDeclaration's init symbol

    • isOriginal

      Declaration

      bool isOriginal;

      used when moving instances to indicate this is this.origin

    • getField

      Declaration

      Expression getField(Type type, uint offset);

      Gets expression at offset of type. Returns NULL if not found.

    • getFieldIndex

      Declaration

      int getFieldIndex(Type type, uint offset);

      Get index of field. Returns -1 if not found.

  • CompoundLiteralExp

    Declaration

    class CompoundLiteralExp: dmd.expression.Expression;

    C11 6.5.2.5 ( type-name ) { initializer-list }

    • initializer

      Declaration

      Initializer initializer;

      initializer-list

  • TypeExp

    Declaration

    class TypeExp: dmd.expression.Expression;

    Mainly just a placeholder

  • ScopeExp

    Declaration

    class ScopeExp: dmd.expression.Expression;

    Mainly just a placeholder of Package, Module, Nspace, and TemplateInstance (including TemplateMixin)

    Discussion

    A template instance that requires IFTI: foo!tiargs(fargs) // foo!tiargs is left until CallExp::semantic() or resolveProperties()

  • TemplateExp

    Declaration

    class TemplateExp: dmd.expression.Expression;

    Mainly just a placeholder

  • NewExp

    Declaration

    class NewExp: dmd.expression.Expression;

    newtype(arguments)

    • argumentList

      Declaration

      ArgumentList argumentList();

      Puts the arguments and names into an ArgumentList for easily passing them around. The fields are still separate for backwards compatibility

  • NewAnonClassExp

    Declaration

    class NewAnonClassExp: dmd.expression.Expression;

    class baseclasses { } (arguments)

  • SymbolExp

    Declaration

    class SymbolExp: dmd.expression.Expression;

  • SymOffExp

    Declaration

    class SymOffExp: dmd.expression.SymbolExp;

    Offset from symbol

  • VarExp

    Declaration

    class VarExp: dmd.expression.SymbolExp;

    Variable

  • OverExp

    Declaration

    class OverExp: dmd.expression.Expression;

    Overload Set

  • FuncExp

    Declaration

    class FuncExp: dmd.expression.Expression;

    Function/Delegate literal

  • DeclarationExp

    Declaration

    class DeclarationExp: dmd.expression.Expression;

    Declaration of a symbol

    Discussion

    D grammar allows declarations only as statements. However in AST representation it can be part of any expression. This is used, for example, during internal syntax re-writes to inject hidden symbols.

  • TypeidExp

    Declaration

    class TypeidExp: dmd.expression.Expression;

    typeid(int)

  • TraitsExp

    Declaration

    class TraitsExp: dmd.expression.Expression;

    _traits(identifier, args...)

  • HaltExp

    Declaration

    class HaltExp: dmd.expression.Expression;

    Generates a halt instruction

    Discussion

    assert(0) gets rewritten to this with CHECKACTION.halt

  • IsExp

    Declaration

    class IsExp: dmd.expression.Expression;

    is(targ id tok tspec) is(targ id == tok2)

  • UnaExp

    Declaration

    abstract class UnaExp: dmd.expression.Expression;

    Base class for unary operators

    Discussion

    https://dlang.org/spec/expression.html#unary-expression

    • incompatibleTypes

      Declaration

      final Expression incompatibleTypes();

      The type for a unary expression is incompatible. Print error message.

      Return Value

      ErrorExp

    • setNoderefOperand

      Declaration

      final void setNoderefOperand();

      Mark the operand as will never be dereferenced, which is useful info for @safe checks. Do before semantic() on operands rewrites them.

  • BinExp

    Declaration

    abstract class BinExp: dmd.expression.Expression;

    Base class for binary operators

    • incompatibleTypes

      Declaration

      final Expression incompatibleTypes();

      The types for a binary expression are incompatible. Print error message.

      Return Value

      ErrorExp

    • setNoderefOperands

      Declaration

      final void setNoderefOperands();

      Mark the operands as will never be dereferenced, which is useful info for @safe checks. Do before semantic() on operands rewrites them.

  • BinAssignExp

    Declaration

    class BinAssignExp: dmd.expression.BinExp;

    Binary operator assignment, += -= *= etc.

  • MixinExp

    Declaration

    class MixinExp: dmd.expression.Expression;

    A string mixin, mixin("x")

    Discussion

    https://dlang.org/spec/expression.html#mixin_expressions

  • ImportExp

    Declaration

    class ImportExp: dmd.expression.UnaExp;

    An import expression, import("file.txt")

    Discussion

    Not to be confused with module imports, import std.stdio, which is an ImportStatement

    https://dlang.org/spec/expression.html#import_expressions

  • AssertExp

    Declaration

    class AssertExp: dmd.expression.UnaExp;

    An assert expression, assert(x == y)

    Discussion

    https://dlang.org/spec/expression.html#assert_expressions

  • ThrowExp

    Declaration

    class ThrowExp: dmd.expression.UnaExp;

    throw <e1> as proposed by DIP 1034.

    Discussion

    Replacement for the deprecated ThrowStatement that can be nested in other expression.

  • DotIdExp

    Declaration

    class DotIdExp: dmd.expression.UnaExp;

  • DotTemplateExp

    Declaration

    class DotTemplateExp: dmd.expression.UnaExp;

    Mainly just a placeholder

  • DotVarExp

    Declaration

    class DotVarExp: dmd.expression.UnaExp;

  • DotTemplateInstanceExp

    Declaration

    class DotTemplateInstanceExp: dmd.expression.UnaExp;

    foo.bar!(args)

  • DelegateExp

    Declaration

    class DelegateExp: dmd.expression.UnaExp;

  • DotTypeExp

    Declaration

    class DotTypeExp: dmd.expression.UnaExp;

  • ArgumentList

    Declaration

    struct ArgumentList;

    The arguments of a function call

    Discussion

    Contains a list of expressions. If it is a named argument, the names list has a non-null entry at the same index.

    • hasNames

      Declaration

      const pure nothrow @nogc @safe bool hasNames();

      Return Value

      whether this argument list contains any named arguments

  • CallExp

    Declaration

    class CallExp: dmd.expression.UnaExp;

    • inDebugStatement

      Declaration

      bool inDebugStatement;

      true if this was in a debug statement

    • ignoreAttributes

      Declaration

      bool ignoreAttributes;

      don't enforce attributes (e.g. call @gc function in @nogc code)

    • isUfcsRewrite

      Declaration

      bool isUfcsRewrite;

      the first argument was pushed in here by a UFCS rewrite

    • argumentList

      Declaration

      ArgumentList argumentList();

      Puts the arguments and names into an ArgumentList for easily passing them around. The fields are still separate for backwards compatibility

    • this

      Declaration

      this(const ref Loc loc, FuncDeclaration fd, Expression earg1);

      Instatiates a new function call expression

      Parameters

      Loc loc

      location

      FuncDeclaration fd

      the declaration of the function to call

      Expression earg1

      the function argument

    • create

      Declaration

      static CallExp create(const ref Loc loc, FuncDeclaration fd, Expression earg1);

      Creates a new function call expression

      Parameters

      Loc loc

      location

      FuncDeclaration fd

      the declaration of the function to call

      Expression earg1

      the function argument

  • calledFunctionType

    Declaration

    TypeFunction calledFunctionType(CallExp ce);

    Get the called function type from a call expression

    Parameters

    CallExp ce

    function call expression. Must have had semantic analysis done.

    Return Value

    called function type, or null if error / no semantic analysis done

  • AddrExp

    Declaration

    class AddrExp: dmd.expression.UnaExp;

    The 'address of' operator, &p

  • PtrExp

    Declaration

    class PtrExp: dmd.expression.UnaExp;

    The pointer dereference operator, *p

  • NegExp

    Declaration

    class NegExp: dmd.expression.UnaExp;

    The negation operator, -x

  • UAddExp

    Declaration

    class UAddExp: dmd.expression.UnaExp;

    The unary add operator, +x

  • ComExp

    Declaration

    class ComExp: dmd.expression.UnaExp;

    The bitwise complement operator, ~x

  • NotExp

    Declaration

    class NotExp: dmd.expression.UnaExp;

    The logical not operator, !x

  • DeleteExp

    Declaration

    class DeleteExp: dmd.expression.UnaExp;

    The delete operator, delete x (deprecated)

    Discussion

    https://dlang.org/spec/expression.html#delete_expressions

  • CastExp

    Declaration

    class CastExp: dmd.expression.UnaExp;

    The type cast operator, cast(T) x

    Discussion

    It's possible to cast to one type while painting to another type

    https://dlang.org/spec/expression.html#cast_expressions

  • VectorExp

    Declaration

    class VectorExp: dmd.expression.UnaExp;

  • VectorArrayExp

    Declaration

    class VectorArrayExp: dmd.expression.UnaExp;

    e1.array property for vectors.

    Discussion

    https://dlang.org/spec/simd.html#properties

  • SliceExp

    Declaration

    class SliceExp: dmd.expression.UnaExp;

    e1 [lwr .. upr]

    Discussion

    https://dlang.org/spec/expression.html#slice_expressions

    • this

      Declaration

      @safe this(const ref Loc loc, Expression e1, IntervalExp ie);

  • ArrayLengthExp

    Declaration

    class ArrayLengthExp: dmd.expression.UnaExp;

    The .length property of an array

  • ArrayExp

    Declaration

    class ArrayExp: dmd.expression.UnaExp;

    e1 [ a0, a1, a2, a3 ,... ]

    Discussion

    https://dlang.org/spec/expression.html#index_expressions

  • DotExp

    Declaration

    class DotExp: dmd.expression.BinExp;

  • CommaExp

    Declaration

    class CommaExp: dmd.expression.BinExp;

    • isGenerated

      Declaration

      const bool isGenerated;

      This is needed because AssignExp rewrites CommaExp, hence it needs to trigger the deprecation.

    • allowCommaExp

      Declaration

      bool allowCommaExp;

      Temporary variable to enable / disable deprecation of comma expression depending on the context. Since most constructor calls are rewritting, the only place where false will be passed will be from the parser.

    • allow

      Declaration

      static @safe void allow(Expression exp);

      If the argument is a CommaExp, set a flag to prevent deprecation messages

      Discussion

      It's impossible to know from CommaExp.semantic if the result will be used, hence when there is a result (type != void), a deprecation message is always emitted. However, some construct can produce a result but won't use it (ExpStatement and for loop increment). Those should call this function to prevent unwanted deprecations to be emitted.

      Parameters

      Expression exp

      An expression that discards its result. If the argument is null or not a CommaExp, nothing happens.

  • IntervalExp

    Declaration

    class IntervalExp: dmd.expression.Expression;

    Mainly just a placeholder

  • DelegatePtrExp

    Declaration

    class DelegatePtrExp: dmd.expression.UnaExp;

    The dg.ptr property, pointing to the delegate's 'context'

    Discussion

    c.f.DelegateFuncptrExp for the delegate's function pointer dg.funcptr

  • DelegateFuncptrExp

    Declaration

    class DelegateFuncptrExp: dmd.expression.UnaExp;

    The dg.funcptr property, pointing to the delegate's function

    Discussion

    c.f.DelegatePtrExp for the delegate's function pointer dg.ptr

  • IndexExp

    Declaration

    class IndexExp: dmd.expression.BinExp;

    e1 [ e2 ]

  • PostExp

    Declaration

    class PostExp: dmd.expression.BinExp;

    The postfix increment/decrement operator, i++ / i--

  • PreExp

    Declaration

    class PreExp: dmd.expression.UnaExp;

    The prefix increment/decrement operator, ++i / --i

  • AssignExp

    Declaration

    class AssignExp: dmd.expression.BinExp;

    The assignment / initialization operator, =

    Note: operator assignment op= has a different base class, BinAssignExp

    • this

      Declaration

      @safe this(const ref Loc loc, Expression e1, Expression e2);

  • LoweredAssignExp

    Declaration

    class LoweredAssignExp: dmd.expression.AssignExp;

    When an assignment expression is lowered to a druntime call this class is used to store the lowering. It essentially behaves the same as an AssignExp, but it is used to not waste space for other AssignExp that are not lowered to anything.

  • ConstructExp

    Declaration

    class ConstructExp: dmd.expression.AssignExp;

  • BlitExp

    Declaration

    class BlitExp: dmd.expression.AssignExp;

    A bit-for-bit copy from e2 to e1

  • AddAssignExp

    Declaration

    class AddAssignExp: dmd.expression.BinAssignExp;

    x += y

  • MinAssignExp

    Declaration

    class MinAssignExp: dmd.expression.BinAssignExp;

    x -= y

  • MulAssignExp

    Declaration

    class MulAssignExp: dmd.expression.BinAssignExp;

    x *= y

  • DivAssignExp

    Declaration

    class DivAssignExp: dmd.expression.BinAssignExp;

    x /= y

  • ModAssignExp

    Declaration

    class ModAssignExp: dmd.expression.BinAssignExp;

    x %= y

  • AndAssignExp

    Declaration

    class AndAssignExp: dmd.expression.BinAssignExp;

    x &= y

  • OrAssignExp

    Declaration

    class OrAssignExp: dmd.expression.BinAssignExp;

    x |= y

  • XorAssignExp

    Declaration

    class XorAssignExp: dmd.expression.BinAssignExp;

    x ^= y

  • PowAssignExp

    Declaration

    class PowAssignExp: dmd.expression.BinAssignExp;

    x ^^= y

  • ShlAssignExp

    Declaration

    class ShlAssignExp: dmd.expression.BinAssignExp;

    x <<= y

  • ShrAssignExp

    Declaration

    class ShrAssignExp: dmd.expression.BinAssignExp;

    x >>= y

  • UshrAssignExp

    Declaration

    class UshrAssignExp: dmd.expression.BinAssignExp;

    x >>>= y

  • CatAssignExp

    Declaration

    class CatAssignExp: dmd.expression.BinAssignExp;

    The ~= operator.

    Discussion

    It can have one of the following operators:

    EXP.concatenateAssign - appending T[] to T[] EXP.concatenateElemAssign - appending T to T[] EXP.concatenateDcharAssign - appending dchar to T[]

    The parser initially sets it to EXP.concatenateAssign, and semantic() later decides which of the three it will be set to.

  • CatElemAssignExp

    Declaration

    class CatElemAssignExp: dmd.expression.CatAssignExp;

    The ~= operator when appending a single element

  • CatDcharAssignExp

    Declaration

    class CatDcharAssignExp: dmd.expression.CatAssignExp;

    The ~= operator when appending a single dchar

  • AddExp

    Declaration

    class AddExp: dmd.expression.BinExp;

    The addition operator, x + y

    Discussion

    https://dlang.org/spec/expression.html#add_expressions

  • MinExp

    Declaration

    class MinExp: dmd.expression.BinExp;

    The minus operator, x - y

    Discussion

    https://dlang.org/spec/expression.html#add_expressions

  • CatExp

    Declaration

    class CatExp: dmd.expression.BinExp;

    The concatenation operator, x ~ y

    Discussion

    https://dlang.org/spec/expression.html#cat_expressions

  • MulExp

    Declaration

    class MulExp: dmd.expression.BinExp;

    The multiplication operator, x * y

    Discussion

    https://dlang.org/spec/expression.html#mul_expressions

  • DivExp

    Declaration

    class DivExp: dmd.expression.BinExp;

    The division operator, x / y

    Discussion

    https://dlang.org/spec/expression.html#mul_expressions

  • ModExp

    Declaration

    class ModExp: dmd.expression.BinExp;

    The modulo operator, x % y

    Discussion

    https://dlang.org/spec/expression.html#mul_expressions

  • PowExp

    Declaration

    class PowExp: dmd.expression.BinExp;

    The 'power' operator, x ^^ y

    Discussion

    https://dlang.org/spec/expression.html#pow_expressions

  • ShlExp

    Declaration

    class ShlExp: dmd.expression.BinExp;

    The 'shift left' operator, x << y

    Discussion

    https://dlang.org/spec/expression.html#shift_expressions

  • ShrExp

    Declaration

    class ShrExp: dmd.expression.BinExp;

    The 'shift right' operator, x >> y

    Discussion

    https://dlang.org/spec/expression.html#shift_expressions

  • UshrExp

    Declaration

    class UshrExp: dmd.expression.BinExp;

    The 'unsigned shift right' operator, x >>> y

    Discussion

    https://dlang.org/spec/expression.html#shift_expressions

  • AndExp

    Declaration

    class AndExp: dmd.expression.BinExp;

    The bitwise 'and' operator, x & y

    Discussion

    https://dlang.org/spec/expression.html#and_expressions

  • OrExp

    Declaration

    class OrExp: dmd.expression.BinExp;

    The bitwise 'or' operator, x | y

    Discussion

    https://dlang.org/spec/expression.html#or_expressions

  • XorExp

    Declaration

    class XorExp: dmd.expression.BinExp;

    The bitwise 'xor' operator, x ^ y

    Discussion

    https://dlang.org/spec/expression.html#xor_expressions

  • LogicalExp

    Declaration

    class LogicalExp: dmd.expression.BinExp;

    The logical 'and' / 'or' operator, X && Y / X || Y

    Discussion

    https://dlang.org/spec/expression.html#andand_expressions https://dlang.org/spec/expression.html#oror_expressions

  • CmpExp

    Declaration

    class CmpExp: dmd.expression.BinExp;

    A comparison operator, < <= > >=

    Discussion

    op is one of: EXP.lessThan, EXP.lessOrEqual, EXP.greaterThan, EXP.greaterOrEqual

    https://dlang.org/spec/expression.html#relation_expressions

  • InExp

    Declaration

    class InExp: dmd.expression.BinExp;

    The in operator, "a" in ["a": 1]

    Note: x !in y is rewritten to !(x in y) in the parser

    https://dlang.org/spec/expression.html#in_expressions

  • RemoveExp

    Declaration

    class RemoveExp: dmd.expression.BinExp;

    Associative array removal, aa.remove(arg)

    Discussion

    This deletes the key e1 from the associative array e2

  • EqualExp

    Declaration

    class EqualExp: dmd.expression.BinExp;

    == and !=

    Discussion

    EXP.equal and EXP.notEqual

    https://dlang.org/spec/expression.html#equality_expressions

  • IdentityExp

    Declaration

    class IdentityExp: dmd.expression.BinExp;

    is and !is

    Discussion

    EXP.identity and EXP.notIdentity

    https://dlang.org/spec/expression.html#identity_expressions

  • CondExp

    Declaration

    class CondExp: dmd.expression.BinExp;

    The ternary operator, econd ? e1 : e2

    Discussion

    https://dlang.org/spec/expression.html#conditional_expressions

  • DefaultInitExp

    Declaration

    class DefaultInitExp: dmd.expression.Expression;

    A special keyword when used as a function's default argument

    Discussion

    When possible, special keywords are resolved in the parser, but when appearing as a default argument, they result in an expression deriving from this base class that is resolved for each function call.

    1. const x = __LINE__; // resolved in the parser void foo(string file = __FILE__, int line = __LINE__); // DefaultInitExp


    https://dlang.org/spec/expression.html#specialkeywords

    • this

      Declaration

      @safe this(const ref Loc loc, EXP op);

      Parameters

      Loc loc

      location

      EXP op

      EXP.prettyFunction, EXP.functionString, EXP.moduleString, EXP.line, EXP.file, EXP.fileFullPath

  • FileInitExp

    Declaration

    class FileInitExp: dmd.expression.DefaultInitExp;

    The __FILE__ token as a default argument

  • LineInitExp

    Declaration

    class LineInitExp: dmd.expression.DefaultInitExp;

    The __LINE__ token as a default argument

  • ModuleInitExp

    Declaration

    class ModuleInitExp: dmd.expression.DefaultInitExp;

    The __MODULE__ token as a default argument

  • FuncInitExp

    Declaration

    class FuncInitExp: dmd.expression.DefaultInitExp;

    The __FUNCTION__ token as a default argument

  • PrettyFuncInitExp

    Declaration

    class PrettyFuncInitExp: dmd.expression.DefaultInitExp;

    The __PRETTY_FUNCTION__ token as a default argument

  • ObjcClassReferenceExp

    Declaration

    class ObjcClassReferenceExp: dmd.expression.Expression;

    Objective-C class reference expression.

    Discussion

    Used to get the metaclass of an Objective-C class, NSObject.Class.

  • GenericExp

    Declaration

    class GenericExp: dmd.expression.Expression;

    C11 6.5.1.1 Generic Selection For ImportC

    • cntlExp

      Declaration

      Expression cntlExp;

      controlling expression of a generic selection (not evaluated)

    • types

      Declaration

      Types* types;

      type-names for generic associations (null entry for default)

    • exps

      Declaration

      Expressions* exps;

      1:1 mapping of typeNames to exps

  • checkModifiable

    Declaration

    Modifiable checkModifiable(Expression exp, Scope* sc, ModifyFlags flag = ModifyFlags.none);

    Parameters: sc: scope flag: 1: do not issue error message for invalid modification 2: the exp is a DotVarExp and a subfield of the leftmost variable is modified

    Return Value

    Whether the type is modifiable

  • isArrayConstruction

    Declaration

    bool isArrayConstruction(const Identifier id);

    Verify if the given identifier is d_array{,set}ctor.

    Parameters

    Identifier id

    the identifier to verify

    Return Value

    true if the identifier corresponds to a construction runtime hook, false otherwise.