wyc.builder

Class CompileTask

java.lang.Object

wyc.builder.CompileTask

All Implemented Interfaces:

wybs.lang.Build.Task, wycc.lang.Feature

public final class CompileTask
extends Object
implements wybs.lang.Build.Task

Responsible for managing the process of turning source files into binary code for execution. Each source file is passed through a pipeline of stages that modify it in a variety of ways. The main stages are:

1. Lexing and Parsing, where the source file is converted into an Abstract Syntax Tree (AST) representation.

2. Name Resolution, where the fully qualified names of all external symbols are determined.

3. Type Propagation, where the types of all expressions are determined by propagation from e.g. declared parameter types.

4. WYIL Generation, where the the AST is converted into the Whiley Intermediate Language (WYIL). A number of passes are then made over this before it is ready for code generation.

5. Code Generation. Here, the executable code is finally generated. This could be Java bytecode, or something else (e.g. JavaScript).

Every stage of the compiler can be configured by setting various options. Stages can also be bypassed (typically for testing) and new ones can be added.

Author:

David J. Pearce

Nested Class Summary

Nested classes/interfaces inherited from interface wycc.lang.Feature

wycc.lang.Feature.Configurable, wycc.lang.Feature.ConfigurationError

Constructor Summary

Constructors

Constructor and Description
CompileTask(wybs.lang.Build.Project project)

Method Summary

Modifier and Type	Method and Description
Set<wyfs.lang.Path.Entry<?>>	build(Collection<wycc.util.Pair<wyfs.lang.Path.Entry<?>,wyfs.lang.Path.Root>> delta, wybs.lang.Build.Graph graph)
boolean	exists(wyfs.lang.Path.ID id)
WyilFile	getModule(wyfs.lang.Path.ID mid) Get the (compiled) module associated with a given module identifier.
WhileyFile	getSourceFile(wyfs.lang.Path.ID mid) Get the source file associated with a given module identifier.
TypeSystem	getTypeSystem() Access the type system object this compile task is using.
boolean	hasModifier(wybs.lang.NameID nid, WhileyFile.Context context, Modifier modifier) Determine whether a named item has a modifier matching one of a given list.
String	id()
List<wyfs.lang.Path.ID>	imports(wyfs.util.Trie key) This method takes a given import declaration, and expands it to find all matching modules.
boolean	isName(wybs.lang.NameID nid) Determine whether a given name exists or not.
boolean	isNameVisible(wybs.lang.NameID nid, WhileyFile.Context context) Determine whether a name is visible in a given context.
boolean	isTypeVisible(wybs.lang.NameID nid, WhileyFile.Context context) Determine whether a named type is fully visible in a given context.
wybs.lang.Build.Project	project()
wyfs.lang.Path.ID	resolveAsModule(String name, WhileyFile.Context context) This method attempts to resolve a name as a module in a given name context.
wybs.lang.NameID	resolveAsName(List<String> names, WhileyFile.Context context) This methods attempts to resolve the given list of names into a single named item (e.g.
wybs.lang.NameID	resolveAsName(String name, WhileyFile.Context context) Responsible for resolve names, types, constants and functions / methods at the global level.
void	setLogger(wycc.util.Logger logger)
Type	toSemanticType(wyal.lang.WyalFile.Type type, WhileyFile.Context context) Convert a Whiley "syntactic" type into a wyil type.

Methods inherited from class java.lang.Object

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

Constructor Detail

CompileTask

public CompileTask(wybs.lang.Build.Project project)

Method Detail

id

public String id()

project

public wybs.lang.Build.Project project()

Specified by:

project in interface wybs.lang.Build.Task

getTypeSystem

public TypeSystem getTypeSystem()

Access the type system object this compile task is using.

Returns:

setLogger

public void setLogger(wycc.util.Logger logger)

build

public Set<wyfs.lang.Path.Entry<?>> build(Collection<wycc.util.Pair<wyfs.lang.Path.Entry<?>,wyfs.lang.Path.Root>> delta,
                                          wybs.lang.Build.Graph graph)
                                   throws IOException

Specified by:

build in interface wybs.lang.Build.Task

Throws:

IOException

exists

public boolean exists(wyfs.lang.Path.ID id)

isName

public boolean isName(wybs.lang.NameID nid)
               throws IOException

Determine whether a given name exists or not.

Parameters:

nid - --- Name ID to check

Returns:

Throws:

IOException

isNameVisible

public boolean isNameVisible(wybs.lang.NameID nid,
                             WhileyFile.Context context)
                      throws IOException

Determine whether a name is visible in a given context. This effectively corresponds to checking whether or not the already name exists in the given context; or, a public or protected named is imported from another file.

Parameters:

nid - Name to check modifiers of

context - Context in which we are trying to access named item

Returns:

True if given context permitted to access name

Throws:

IOException

isTypeVisible

public boolean isTypeVisible(wybs.lang.NameID nid,
                             WhileyFile.Context context)
                      throws IOException

Determine whether a named type is fully visible in a given context. This effectively corresponds to checking whether or not the already type exists in the given context; or, a public type is imported from another file.

Parameters:

nid - Name to check modifiers of

context - Context in which we are trying to access named item

Returns:

True if given context permitted to access name

Throws:

IOException

hasModifier

public boolean hasModifier(wybs.lang.NameID nid,
                           WhileyFile.Context context,
                           Modifier modifier)
                    throws IOException

Determine whether a named item has a modifier matching one of a given list. This is particularly useful for checking visibility (e.g. public, private, etc) of named items.

Parameters:

nid - Name to check modifiers of

context - Context in which we are trying to access named item

modifiers -

Returns:

True if given context permitted to access name

Throws:

IOException

imports

public List<wyfs.lang.Path.ID> imports(wyfs.util.Trie key)
                                throws wybs.util.ResolveError

This method takes a given import declaration, and expands it to find all matching modules.

Parameters:

imp -

Returns:

Throws:

wybs.util.ResolveError

getSourceFile

public WhileyFile getSourceFile(wyfs.lang.Path.ID mid)
                         throws IOException

Get the source file associated with a given module identifier. If the source file does not exist, null is returned.

Parameters:

mid -

Returns:

Throws:

IOException

getModule

public WyilFile getModule(wyfs.lang.Path.ID mid)
                   throws IOException

Get the (compiled) module associated with a given module identifier. If the module does not exist, a resolve error is thrown.

Parameters:

mid -

Returns:

Throws:

IOException

resolveAsName

public wybs.lang.NameID resolveAsName(String name,
                                      WhileyFile.Context context)
                               throws IOException,
                                      wybs.util.ResolveError

Responsible for resolve names, types, constants and functions / methods at the global level. Resolution is determined by the context in which a given name/type/constant/function/method appears. That is, what imports are active in the enclosing WhileyFile. For example, consider this:

 import whiley.lang.*

 type nat is Int.uint

 import whiley.ui.*
 

In this example, the statement "import whiley.lang.*" is active for the type declaration, whilst the statement " import whiley.ui.*". The context of the type declaration is everything in the enclosing file up to the declaration itself. Therefore, in resolving the name Int.uint, this will examine the package whiley.lang to see whether a compilation unit named "Int" exists. If so, it will then resolve the name Int.uint to whiley.lang.Int.uint.

Parameters:

name - A module name without package specifier.

context - --- context in which to resolve.

Returns:

The resolved name.

Throws:

IOException - if it couldn't resolve the name

wybs.util.ResolveError

resolveAsName

public wybs.lang.NameID resolveAsName(List<String> names,
                                      WhileyFile.Context context)
                               throws IOException,
                                      wybs.util.ResolveError

This methods attempts to resolve the given list of names into a single named item (e.g. type, method, constant, etc). For example, ["whiley","lang","Math","max"] would be resolved, since whiley.lang.Math.max is a valid function name. In contrast, ["whiley","lang","Math"] does not resolve since whiley.lang.Math refers to a module.

Parameters:

names - A list of components making up the name, which may include the package and enclosing module.

context - --- context in which to resolve *

Returns:

The resolved name.

Throws:

IOException - if it couldn't resolve the name

wybs.util.ResolveError

resolveAsModule

public wyfs.lang.Path.ID resolveAsModule(String name,
                                         WhileyFile.Context context)
                                  throws IOException,
                                         wybs.util.ResolveError

This method attempts to resolve a name as a module in a given name context.

Parameters:

name - --- name to be resolved

context - --- context in which to resolve

Returns:

Throws:

IOException

wybs.util.ResolveError

toSemanticType

public Type toSemanticType(wyal.lang.WyalFile.Type type,
                           WhileyFile.Context context)
                    throws wybs.util.ResolveError,
                           IOException

Convert a Whiley "syntactic" type into a wyil type. This is essentially a straightforward process. The only complication is that the names for nominal types have to be properly resolved.

Parameters:

type - The type to be converted

Returns:

A Wyil Type equivalent to the original Whiley type

Throws:

wybs.util.ResolveError - If a named type within this condition cannot be resolved within the enclosing project.

IOException