org.stekikun.dolmen.codegen

Class SourceMapping

java.lang.Object

org.stekikun.dolmen.codegen.SourceMapping

public final class SourceMapping
extends Object

This class stores a mapping from range of positions in a generated file (typically a generated Java lexer or parser) to corresponding positions in a source file (typically a Dolmen lexer or parser description file), or even several source files.

The point of this information is to keep track of where semantic actions (see Extent) end up in generated files, to be able to translate features that rely on positions in generated files (errors, markers, stacktrace information) back to the corresponding positions in the source files if possible.

Author:

Stéphane Lescuyer

Nested Class Summary

Nested Classes

Modifier and Type	Class and Description
static class	SourceMapping.Mapping A mapping describes a link between the range described by SourceMapping.Mapping.offset and SourceMapping.Mapping.length in the generated file and the region of the same length starting at position SourceMapping.Mapping.origin in the source file.
static class	SourceMapping.Origin An instance of this class describes the origin of some region of generated code in terms of the source region from which it originated.

Constructor Summary

Constructors

Constructor and Description
SourceMapping(String generated)

Method Summary

Modifier and Type	Method and Description
void	add(int offset, int length, LexBuffer.Position origin, @Nullable CExtent extent) Adds a new mapping to this, describing that the range starting at position offset and spanning length bytes corresponds to the range of the same length at position origin in the original source.
void	forEach(Consumer<? super SourceMapping.Mapping> consumer) Iterates on all known mappings and applies consumer on each one
@Nullable SourceMapping.Origin	map(int offset, int length) Tries to map the region described by offset and length to the original source via the mappings known in this instance.
String	toString()

Methods inherited from class java.lang.Object

clone, equals, finalize, getClass, hashCode, notify, notifyAll, wait, wait, wait

Constructor Detail

SourceMapping

public SourceMapping(String generated)

Parameters:

generated - a name describing the input being mapped Constructs a fresh and empty SourceMapping describing mapping regions of generated to regions of one or several original sources

Method Detail

add

public void add(int offset,
                int length,
                LexBuffer.Position origin,
                @Nullable CExtent extent)

Adds a new mapping to this, describing that the range starting at position offset and spanning length bytes corresponds to the range of the same length at position origin in the original source.

If the mapped region stems from expanding and instantiating the source region, the structure of the instantiation is given by extent. Otherwise extent must be null.

Parameters:

offset -

length -

origin -

extent -

toString

public String toString()

Overrides:

toString in class Object

forEach

public void forEach(Consumer<? super SourceMapping.Mapping> consumer)

Iterates on all known mappings and applies consumer on each one

Parameters:

consumer -

map

public @Nullable SourceMapping.Origin map(int offset,
                                          int length)

Tries to map the region described by offset and length to the original source via the mappings known in this instance.

The returned origin does not necessarily match the given region's contents exactly, as the latter may be the result of instantiating holes in semantic actions.

Parameters:

offset -

length -

Returns:

the origin in source where the desired range stemmed from, or null if the described range is not entirely mapped in any of these source mappings

See Also:

SourceMapping.Origin