Encapsulates the LeMP engine, a simple LISP-style macro processor, suitable for running LLLPG and other lexical macros. More...

Source file:

/Main/LeMP/MacroProcessor.cs

Remarks

Encapsulates the LeMP engine, a simple LISP-style macro processor, suitable for running LLLPG and other lexical macros.

MacroProcessor itself only cares about a few nodes including #importMacros and #unimportMacros, and { braces } (for scoping the #import statements). The macro processor should be configured with any needed macros like this:

var prelude = typeof(LeMP.Prelude.BuiltinMacros); // the default prelude
var MP = new MacroProcessor(prelude, sink);
MP.AddMacros(typeof(LeMP.StandardMacros).Assembly);
MP.PreOpenedNamespaces.Add((Symbol) "LeMP.Prelude"); // already done for you
MP.PreOpenedNamespaces.Add((Symbol) "LeMP");

In order for the input code to have access to macros, two steps are necessary: you have to add the macro classes with AddMacros and then you have to import the namespace that contains the class(es). Higher-level code (e.g. Compiler) can define "always-open" namespaces by adding entries to PreOpenedNamespaces, and the code being processed can open additional namespaces with a #importMacros(Namespace) statement.

MacroProcessor is not aware of any distinction between "statements" and "expressions"; it will run macros no matter where they are located, whether as standalone statements, attributes, or arguments to functions.

MacroProcessor's main responsibilities are to keep track of a table of registered macros (call AddMacros to register more), to keep track of which namespaces are open, to scan the input for macros to call; and to control the printout of messages.

This class processes a batch of files at once. Call either ProcessSynchronously or ProcessParallel. Parallelizing on a file-by-file basis is easy; each source file is completely independent, since no semantic analysis is being done.

Public fields
int	MaxExpansions = 255

MMap< object, object >	DefaultScopedProperties = new MMap<object, object>()
	Default values of scoped properties. More...

Properties
IMessageSink	Sink `[get, set]`

static MacroProcessor	Current `[get]`
	Returns the `MacroProcessor` running on the current thread, or null if none. More...

ICollection< Symbol >	PreOpenedNamespaces `[get]`
	Macros in these namespaces will be available without an explicit import command (#importMacros). By default this list has one item: @LeMP.Prelude (i.e. (Symbol)"LeMP.Prelude") More...

TimeSpan	AbortTimeout `[get, set]`

static int	NextTempCounter `[get]`
	Gets the next number to use as a suffix for temporary variables (without incrementing). More...

Public Member Functions
	MacroProcessor (IMessageSink sink)
	Initializes MacroProcessor with default prelude. More...

	MacroProcessor (IMessageSink sink, Type prelude)
	Initializes MacroProcessor. More...

int	AddMacros (Type type)

int	AddMacros (Assembly assembly, bool writeToSink=true)

LNodeList	ProcessSynchronously (LNodeList stmts)
	Processes a list of nodes directly on the current thread. More...

void	ProcessSynchronously (IReadOnlyList< InputOutput > sourceFiles, Action< InputOutput > onProcessed=null)
	Processes source files one at a time (may be easier for debugging). More...

void	ProcessParallel (IReadOnlyList< InputOutput > sourceFiles, Action< InputOutput > onProcessed=null)
	Processes source files in parallel. All files are fully processed before the method returns. More...

Task< LNodeList >[]	ProcessAsync (IReadOnlyList< InputOutput > sourceFiles, Action< InputOutput > onProcessed=null)
	Processes source files in parallel using .NET Tasks. The method returns immediately. More...

Static Public Member Functions
static int	IncrementTempCounter ()
	Gets the next number to use as a suffix for temporary variables, then increments it. More...

Constructor & Destructor Documentation

◆ MacroProcessor() [1/2]

LeMP.MacroProcessor.MacroProcessor ( IMessageSink sink )

inline

Initializes MacroProcessor with default prelude.

◆ MacroProcessor() [2/2]

LeMP.MacroProcessor.MacroProcessor	(	IMessageSink	sink,
		Type	prelude
	)

inline

Initializes MacroProcessor.

Parameters

sink	The destination for warning and error messages. NOTE: this class can process files in parallel. Consider using a thread-safe implementation of IMessageSink.
prelude	An initial type from which to add macros. Omit this parameter to use typeof(LeMP.Prelude.BuiltinMacros).

References LeMP.MacroProcessor.PreOpenedNamespaces.

Member Function Documentation

◆ IncrementTempCounter()

static int LeMP.MacroProcessor.IncrementTempCounter ( )

inlinestatic

Gets the next number to use as a suffix for temporary variables, then increments it.

MacroProcessor currently starts this counter at 10 to avoid collisions with names like tmp_2 and tmp_3 that might be names chosen by a developer; tmp_10 is much less likely to collide.

References LeMP.MacroProcessor.NextTempCounter.

◆ ProcessAsync()

Task<LNodeList> [] LeMP.MacroProcessor.ProcessAsync	(	IReadOnlyList< InputOutput >	sourceFiles,
		Action< InputOutput >	onProcessed = `null`
	)

inline

Processes source files in parallel using .NET Tasks. The method returns immediately.

References Loyc.Threading.ThreadEx.PropagateVariables().

Referenced by LeMP.MacroProcessor.ProcessParallel().

◆ ProcessParallel()

void LeMP.MacroProcessor.ProcessParallel	(	IReadOnlyList< InputOutput >	sourceFiles,
		Action< InputOutput >	onProcessed = `null`
	)

inline

Processes source files in parallel. All files are fully processed before the method returns.

References LeMP.MacroProcessor.ProcessAsync().

Referenced by LeMP.Compiler.Run().

◆ ProcessSynchronously() [1/2]

void LeMP.MacroProcessor.ProcessSynchronously	(	IReadOnlyList< InputOutput >	sourceFiles,
		Action< InputOutput >	onProcessed = `null`
	)

inline

Processes source files one at a time (may be easier for debugging).

◆ ProcessSynchronously() [2/2]

LNodeList LeMP.MacroProcessor.ProcessSynchronously ( LNodeList stmts )

inline

Processes a list of nodes directly on the current thread.

Note: AbortTimeout doesn't work when using this overload.

Referenced by LeMP.Compiler.Run().

Member Data Documentation

◆ DefaultScopedProperties

MMap<object, object> LeMP.MacroProcessor.DefaultScopedProperties = new MMap<object, object>()

Default values of scoped properties.

Code being processed can look up a scoped property named "N" with #getScopedProperty("N") in LESv2 or EC#. This map is empty by default. Scoped properties are "scoped" in the sense that setting a property with #setScopedProperty(keyLiteral, valueLiteral) takes effect only until the end of the braced block in which it appears.

The @#inputFolder and @#inputFileName properties (note: @ is EC# syntax for Symbol) are not normally stored in this collection; when you use ProcessSynchronously or ProcessParallel, @#inputFolder and @#inputFileName are set according to the folder and filename in InputOutput.FileName. However, @#inputFolder is not set if the filename has no folder component, so this collection could be used to provide a value of @#inputFolder in that case.

Property Documentation

◆ Current

MacroProcessor LeMP.MacroProcessor.Current

staticget

Returns the MacroProcessor running on the current thread, or null if none.

◆ NextTempCounter

int LeMP.MacroProcessor.NextTempCounter

staticget

Gets the next number to use as a suffix for temporary variables (without incrementing).

Referenced by LeMP.MacroProcessor.IncrementTempCounter().

◆ PreOpenedNamespaces

ICollection<Symbol> LeMP.MacroProcessor.PreOpenedNamespaces

get

Macros in these namespaces will be available without an explicit import command (#importMacros). By default this list has one item: @LeMP.Prelude (i.e. (Symbol)"LeMP.Prelude")

Referenced by LeMP.Compiler.AddStdMacros(), and LeMP.MacroProcessor.MacroProcessor().

Remarks

Public fields

Properties

Public Member Functions

Static Public Member Functions

Constructor & Destructor Documentation

◆ MacroProcessor() [1/2]

◆ MacroProcessor() [2/2]

Member Function Documentation

◆ IncrementTempCounter()

◆ ProcessAsync()

◆ ProcessParallel()

◆ ProcessSynchronously() [1/2]

◆ ProcessSynchronously() [2/2]

Member Data Documentation

◆ DefaultScopedProperties

Property Documentation

◆ Current

◆ NextTempCounter

◆ PreOpenedNamespaces