Context provides an API for macro programming.
It contains common functions that interact with the macro interpreter to query or set information. Other API functions are available in the tools classes:
Static methods
staticaddResource(name:String, data:Bytes):Void
Available on macro, neko
Makes resource data
available as name
.
The resource is then available using the haxe.macro.Resource
API.
If a previous resource was bound to name
, it is overwritten.
Compilation server : when using the compilation server, the resource is bound
to the Haxe module which calls the macro, so it will be included again if
that module is reused. If this resource concerns several modules, prefix its
name with a $
sign, this will bind it to the macro module instead.
staticcontainsDisplayPosition(pos:Position):Bool
Available on macro, neko
Check if current display position is within pos
.
staticcurrentPos():Position
Available on macro, neko
Returns the position at which the macro was called.
staticdefineModule(modulePath:String, types:Array<TypeDefinition>, ?imports:Array<ImportExpr>, ?usings:Array<TypePath>):Void
Available on macro, neko
Defines a new module as modulePath
with several TypeDefinition
types
. This is analogous to defining a .hx file.
The individual types
can reference each other and any identifier
respects the imports
and usings
as usual, expect that imports are
not allowed to have .*
wildcards or as s
shorthands.
Usage of this function from initialization macros is deprecated and may
cause compilation server issues. Use Context.onAfterInitMacros
to
run your code once typer is ready to be used.
staticdefineType(t:TypeDefinition, ?moduleDependency:String):Void
Available on macro, neko
Defines a new type from TypeDefinition
t
.
If moduleDependency
is given and is not null
, it should contain
a module path that will be used as a dependency for the newly defined module
instead of the current module.
Usage of this function from initialization macros is deprecated and may
cause compilation server issues. Use Context.onAfterInitMacros
to
run your code once typer is ready to be used.
staticdefined(s:String):Bool
Available on macro, neko
Tells if the conditional compilation flag s
has been set.
Compiler flags are set using the -D
command line parameter, or
by calling haxe.macro.Compiler.define
.
See also:
staticdefinedValue(key:String):Null<String>
Available on macro, neko
Returns the value defined for the conditional compilation flag key
.
If no value is defined for key
, null
is returned.
Compiler flags values are set using the -D key=value
command line
parameter, or by calling haxe.macro.Compiler.define
.
The default value is "1"
.
See also:
staticerror(msg:String, pos:Position, depth:Int = 0):Dynamic
Available on macro, neko
Displays a compilation error msg
at the given Position
pos
and aborts the current macro call.
staticfatalError(msg:String, pos:Position, depth:Int = 0):Dynamic
Available on macro, neko
Displays a compilation error msg
at the given Position
pos
and aborts the compilation.
staticfilterMessages(predicate:Message ‑> Bool):Void
Available on macro, neko
Filters all current info/warning messages. Filtered out messages will not be displayed by the compiler.
staticfollow(t:Type, ?once:Bool):Type
Available on macro, neko
Follows a type.
See haxe.macro.TypeTools.follow
for details.
Usage of this function from initialization macros is deprecated and may
cause compilation server issues. Use Context.onAfterInitMacros
to
run your code once typer is ready to be used.
staticfollowWithAbstracts(t:Type, once:Bool = false):Type
Available on macro, neko
Follows a type, including abstracts' underlying implementation
See haxe.macro.TypeTools.followWithAbstracts
for details.
Usage of this function from initialization macros is deprecated and may
cause compilation server issues. Use Context.onAfterInitMacros
to
run your code once typer is ready to be used.
staticgetAllModuleTypes():Array<ModuleType>
Available on macro, neko
Returns an array of module types to be generated in the output.
This list may change depending on the phase of compilation and should not be treated as conclusive until the generation phase.
Modifying the returned array has no effect on the compilation.
Usage of this function from initialization macros is deprecated and may
cause compilation server issues. Use Context.onAfterInitMacros
to
run your code once typer is ready to be used.
staticgetBuildFields():Array<Field>
Available on macro, neko
Returns an Array
of fields of the class which is to be built.
This is only defined for @:build/@:autoBuild
macros.
staticgetCallArguments():Null<Array<Expr>>
Available on macro, neko
Returns the call arguments that lead to the invocation of the current
@:genericBuild
macro, if available.
Returns null
if the current macro is not a @:genericBuild
macro.
staticgetClassPath():Array<String>
Available on macro, neko
Returns an Array
of current class paths in the order of their
declaration.
Modifying the returned array has no effect on the compiler. Class paths
can be added using haxe.macro.Compiler.addClassPath
.
staticgetDefines():Map<String, String>
Available on macro, neko
Returns a map of all conditional compilation flags that have been set.
Compiler flags are set using the -D
command line parameter, or
by calling haxe.macro.Compiler.define
.
Modifying the returned map has no effect on the compiler.
See also:
staticgetLocalClass():Null<Ref<ClassType>>
Available on macro, neko
Returns the current class in which the macro was called.
If no such class exists, null
is returned.
staticgetLocalImports():Array<ImportExpr>
Available on macro, neko
Returns an Array
of all imports in the context the macro was called.
Modifying the returned array has no effect on the compiler.
staticgetLocalMethod():Null<String>
Available on macro, neko
Returns the name of the method from which the macro was called.
If no such method exists, null
is returned.
staticgetLocalModule():String
Available on macro, neko
Returns the current module path in/on which the macro was called.
staticgetLocalType():Null<Type>
Available on macro, neko
Returns the current type in/on which the macro was called.
If no such type exists, null
is returned.
staticgetLocalUsing():Array<Ref<ClassType>>
Available on macro, neko
Returns an Array
of classes which are available for using
usage in
the context the macro was called.
Modifying the returned array has no effect on the compiler.
staticgetLocalVars():Map<String, Type>
Available on macro, neko
Returns a map of local variables accessible in the context the macro was called.
The keys of the returned map are the variable names, the values are their types.
Modifying the returned map has no effect on the compiler.
staticgetMacroStack():Array<Position>
Available on macro, neko
Get the call stack (excluding the call to Context.getMacroStack()
that led to current macro.
staticgetMainExpr():Null<TypedExpr>
Available on macro, neko
Returns the typed expression of the call to the main function.
This function will only work in the generation phase. Any calls
made outside a function passed to haxe.macro.Context.onGenerate
or haxe.macro.Context.onAfterGenerate
will return null
.
staticgetMessages():Array<Message>
Available on macro, neko
Gets a list of all current compilation info/warning messages.
staticgetModule(name:String):Array<Type>
Available on macro, neko
Resolves a module identified by name
and returns an Array
of all
its contained types.
The resolution follows the usual class path rules where the last declared class path has priority.
If no module can be found, an exception of type String
is thrown.
Usage of this function from initialization macros is deprecated and may
cause compilation server issues. Use Context.onAfterInitMacros
to
run your code once typer is ready to be used.
staticgetPosInfos(p:Position):{min:Int, max:Int, file:String}
Available on macro, neko
Returns the information stored in Position
p
.
staticgetResources():Map<String, Bytes>
Available on macro, neko
Returns a map of all registered resources for this compilation unit.
Modifying the returned map has no effect on the compilation, use
haxe.macro.Context.addResource
to add new resources to the compilation unit.
staticgetType(name:String):Type
Available on macro, neko
Resolves a type identified by name
.
The resolution follows the usual class path rules where the last declared class path has priority.
If no type can be found, an exception of type String
is thrown.
Usage of this function from initialization macros is deprecated and may
cause compilation server issues. Use Context.onAfterInitMacros
to
run your code once typer is ready to be used.
staticgetTypedExpr(t:TypedExpr):Expr
Available on macro, neko
Returns a syntax-level expression corresponding to typed expression t
.
This process may lose some information.
Usage of this function from initialization macros is deprecated and may
cause compilation server issues. Use Context.onAfterInitMacros
to
run your code once typer is ready to be used.
staticinfo(msg:String, pos:Position, depth:Int = 0):Void
Available on macro, neko
Displays a compilation info msg
at the given Position
pos
.
staticinitMacrosDone():Bool
Available on macro, neko
Check if compiler is past initializations macros or not. When it is, configuration phase is over and parsing/typing can start.
staticmakeExpr(v:Dynamic, pos:Position):Expr
Available on macro, neko
Builds an expression from v
.
This method generates AST nodes depending on the macro-runtime value of
v
. As such, only basic types and enums are supported and the behavior
for other types is undefined.
The provided Position
pos
is used for all generated inner AST nodes.
staticmakeMonomorph():Type
Available on macro, neko
Creates and returns a new instance of monomorph (TMono
) type.
Returned monomorph can be used with e.g. Context.unify
to make the compiler
bind the monomorph to an actual type and let macro further process the resulting type.
Usage of this function from initialization macros is deprecated and may
cause compilation server issues. Use Context.onAfterInitMacros
to
run your code once typer is ready to be used.
staticmakePosition(inf:{min:Int, max:Int, file:String}):Position
Available on macro, neko
Builds a Position
from inf
.
staticonAfterGenerate(callback:() ‑> Void):Void
Available on macro, neko
Adds a callback function callback
which is invoked after the compiler
generation phase.
Compilation has completed at this point and cannot be influenced anymore. However, contextual information is still available.
Note: the callback is still invoked when generation is disabled with --no-output
.
staticonAfterInitMacros(callback:() ‑> Void):Void
Available on macro, neko
Adds a callback function callback
which is invoked after the compiler
is done running initialization macros, when typing begins.
onAfterInitMacros
should be used to delay typer-dependant code from
your initialization macros, to properly separate configuration phase and
actual typing.
staticonAfterTyping(callback:Array<ModuleType> ‑> Void):Void
Available on macro, neko
Adds a callback function callback
which is invoked after the compiler
is done typing, but before optimization. The callback receives the types
which have been typed.
It is possible to define new types in the callback, in which case it will be called again with the new types as argument.
staticonGenerate(callback:Array<Type> ‑> Void, persistent:Bool = true):Void
Available on macro, neko
Adds a callback function callback
which is invoked after the
compiler's typing phase, just before its generation phase.
The callback receives an Array
containing all types which are about
to be generated. Modifications are limited to metadata, it is mainly
intended to obtain information.
By default, the callback is made before types are stored in the compilation
server, if active. This means that any effect persists for the next compilation.
If persistent
is set to false
, changes to types made by the callback only
affect the current compilation. If no compilation server is used, this flag has
no effect.
Note: the callback is still invoked when generation is disabled with --no-output
.
staticonTypeNotFound(callback:String ‑> TypeDefinition):Void
Available on macro, neko
Adds a callback function callback
which is invoked when a type name
cannot be resolved.
The callback may return a type definition, which is then used for the
expected type. If it returns null
, the type is considered to still not
exist.
staticparse(expr:String, pos:Position):Expr
Available on macro, neko
Parses expr
as Haxe code, returning the corresponding AST.
String interpolation of single quote strings within expr
is not
supported.
The provided Position
pos
is used for all generated inner AST nodes.
staticparseInlineString(expr:String, pos:Position):Expr
Available on macro, neko
Similar to parse
, but error positions are reported within the provided
String expr
.
staticregisterModuleDependency(modulePath:String, externFile:String):Void
Available on macro, neko
Manually adds a dependency between module modulePath
and an external
file externFile
.
This affects the compilation cache, causing the module to be typed if
externFile
has changed.
Has no effect if the compilation cache is not used.
Usage of this function from initialization macros is deprecated and may
cause compilation server issues. Use Context.onAfterInitMacros
to
run your code once typer is ready to be used.
staticregisterModuleReuseCall(modulePath:String, macroCall:String):Void
Available on macro, neko
staticreportError(msg:String, pos:Position, depth:Int = 0):Void
Available on macro, neko
Displays a compilation error msg
at the given Position
pos
without aborting the current macro call.
staticresolveComplexType(t:ComplexType, p:Position):ComplexType
Available on macro, neko
Resolve type t
and returns the corresponding ComplexType
.
Resolving the type may result in a compiler error which can be
caught using try ... catch
.
Resolution is performed based on the current context in which the macro is called.
The difference with resolveType
is that it only performs type resolution, it does not
build any type or trigger macros.
staticresolvePath(file:String):String
Available on macro, neko
Resolves a file name file
based on the current class paths.
The resolution follows the usual class path rules where the last declared class path has priority.
If a class path was declared relative, this method returns the relative file path. Otherwise it returns the absolute file path.
If no type can be found, an exception of type String
is thrown.
staticresolveType(t:ComplexType, p:Position):Type
Available on macro, neko
Resolve type t
and returns the corresponding Type
.
Resolving the type may result in a compiler error which can be
caught using try ... catch
.
Resolution is performed based on the current context in which the macro is called.
Usage of this function from initialization macros is deprecated and may
cause compilation server issues. Use Context.onAfterInitMacros
to
run your code once typer is ready to be used.
staticstoreExpr(e:Expr):Expr
Available on macro, neko
Types expression e
, stores the resulting typed expression internally and
returns a syntax-level expression that can be returned from a macro and
will be replaced by the stored typed expression.
If e
is null
or invalid, an exception is thrown.
A call to storeExpr(e)
is equivalent to storeTypedExpr(typeExpr(e))
without
the overhead of encoding and decoding between regular and macro runtime.
NOTE: the returned value references an internally stored typed expression that is reset between compilations, so care should be taken when storing the expression returned by this method in a static variable and using the compilation server.
Usage of this function from initialization macros is deprecated and may
cause compilation server issues. Use Context.onAfterInitMacros
to
run your code once typer is ready to be used.
staticstoreTypedExpr(t:TypedExpr):Expr
Available on macro, neko
Store typed expression t
internally and give a syntax-level expression
that can be returned from a macro and will be replaced by the stored
typed expression.
If t
is null
or invalid, an exception is thrown.
NOTE: the returned value references an internally stored typed expression that is reset between compilations, so care should be taken when storing the expression returned by this method in a static variable and using the compilation server.
Usage of this function from initialization macros is deprecated and may
cause compilation server issues. Use Context.onAfterInitMacros
to
run your code once typer is ready to be used.
statictimer(id:String):() ‑> Void
Available on macro, neko
Creates a timer which will be printed in the compilation report
if --times
compilation argument is set.
Note that a timer may be omitted from the report if the amount of time measured is too small.
This method immediately starts a timer and returns a function to stop it:
var stopTimer = haxe.macro.Context.timer("my heavy task");
runTask();
stopTimer();
statictoComplexType(t:Type):Null<ComplexType>
Available on macro, neko
Returns the ComplexType
corresponding to the given Type
t
.
See haxe.macro.TypeTools.toComplexType
for details.
statictypeAndStoreExpr(e:Expr):{type:Ref<Type>, expr:Expr}
Available on macro, neko
This function works like storeExpr
, but also returns access to the expression's
type through the type
field of the return value.
Usage of this function from initialization macros is deprecated and may
cause compilation server issues. Use Context.onAfterInitMacros
to
run your code once typer is ready to be used.
statictypeExpr(e:Expr):TypedExpr
Available on macro, neko
Types expression e
and returns the corresponding TypedExpr
.
Typing the expression may result in a compiler error which can be
caught using try ... catch
. Note that not all compiler errors can
be caught this way because the compiler might delay various checks
to a later stage, at which point the exception handler is no longer
active.
Usage of this function from initialization macros is deprecated and may
cause compilation server issues. Use Context.onAfterInitMacros
to
run your code once typer is ready to be used.
statictypeof(e:Expr):Type
Available on macro, neko
Types expression e
and returns its type.
Typing the expression may result in a compiler error which can be
caught using try ... catch
.
Usage of this function from initialization macros is deprecated and may
cause compilation server issues. Use Context.onAfterInitMacros
to
run your code once typer is ready to be used.
staticunify(t1:Type, t2:Type):Bool
Available on macro, neko
Tries to unify t1
and t2
and returns true
if successful.
Usage of this function from initialization macros is deprecated and may
cause compilation server issues. Use Context.onAfterInitMacros
to
run your code once typer is ready to be used.
staticwarning(msg:String, pos:Position, depth:Int = 0):Void
Available on macro, neko
Displays a compilation warning msg
at the given Position
pos
.
staticwithImports<X>(imports:Array<String>, usings:Array<String>, code:() ‑> X):X
Available on macro, neko
Executes code
in a context that has imports
and usings
added.
This is equivalent to temporarily having import
and using
statements in a file. These
are only active during the execution of code
and do not affect anything afterwards. This
is true even if code
throws an exception.
If any argument is null
, the result is unspecified.
Usage of this function from initialization macros is deprecated and may
cause compilation server issues. Use Context.onAfterInitMacros
to
run your code once typer is ready to be used.
staticwithOptions<X>(options:{allowTransform:Null<Bool>, allowInlining:Null<Bool>}, code:() ‑> X):X
Available on macro, neko
Executes code
in a context that has some compiler options set, restore the compiler to its
default behavior afterwards.
allowInlining
: enable or disable inlining during typing with typeExpr
.
allowTransform
: when disabled, the code typed with typeExpr
will be almost exactly the same
as the input code. This will disable some abstract types transformations.
Usage of this function from initialization macros is deprecated and may
cause compilation server issues. Use Context.onAfterInitMacros
to
run your code once typer is ready to be used.