Package eu.bandm.tools.d2d2.base

Class FirstCalculator

java.lang.Object

eu.bandm.tools.d2d2.model.MATCH_ONLY_00

eu.bandm.tools.d2d2.model.SinglePhase

eu.bandm.tools.d2d2.base.Navigate.VisitReachable<Object>

eu.bandm.tools.d2d2.base.FirstCalculator

public class FirstCalculator
extends Navigate.VisitReachable<Object>

Sets up constants in each Expression, which cache structural properties of the syntax for later parsing.

• The ".firsts : String -> (Expression+int)" director map (this points to sub-expressions of an ALT or PERM or to starting position numbers of a SEQU!)
• whether character data is accepted
• whether epsilon accepted (Expression.canProduceEpsilon is initialized to false and overwritten here to true, if appropriate.)

During this, LL(1) violations are detected.

Visiting starts with the (externally requested) top-level module and follows ONLY references (to declarations contained anywhere!)

ATTENTION: Does NOT visit the expressions X in "import _ from _ ^ ( X / _)"

The "result" mechanism of VisitReachable is not used.

Field Summary

Fields

Modifier and Type	Field	Description
(package private) TagsRegExp	currentdef	Required for error diagnosis only.
protected MessageReceiver<SimpleMessage<XMLDocumentIdentifier>>	msg	Evident

Fields inherited from class eu.bandm.tools.d2d2.base.Navigate.VisitReachable

done, result, todo

Fields inherited from class eu.bandm.tools.d2d2.model.MATCH_ONLY_00

_visitor_debug_stream, partial

Constructor Summary

Constructors

Constructor	Description
FirstCalculator(MessageReceiver<SimpleMessage<XMLDocumentIdentifier>> msg)	Evident
FirstCalculator(MessageReceiver<SimpleMessage<XMLDocumentIdentifier>> msg, @Opt ModuleRegistry modreg)	Evident

Method Summary

Modifier and Type	Method	Description
void	action(Alt alt)	Fill the director maps to the disjunction of all directors of the components.
void	action(CharsRegExp def)	No operation necessary.
void	action(Empty x)	Only mark as visited.
void	action(Enumeration def)	No operation necessary.
void	action(Insertion x)	Mark as visited and set the director maps.
void	action(Opt x)	Copy the directors into the compound expression "x" from its component.
void	action(Pcdata x)	Mark as visited and set the director maps.
void	action(Perm x)	Fill the director maps to the disjunction of all directors of the components.
void	action(Plus x)	Copy the directors into the compound expression "x" from its component.
void	action(Reference ref)	Put "tag->expr" into the directors map for later parsing.
void	action(Seq x)	Fill the director maps of a sequence expression, depending on the possible epsilon-results of its components.
void	action(Star x)	Copy the directors into the compound expression "x" from its component.
void	action(TagsRegExp def)	Memorize location (for messages) and descend into the expression.
protected void	addFromTo(Expression from, Expression to, boolean isalt)	"From" is the component expression FROM which the director map is copied inTO the map ruling the compond expression called "to".d
protected void	copyMult(GrUnary x, boolean canEps)	Copy the directors into a compound expression "x" from its component.
protected void	error(Location<XMLDocumentIdentifier> loc, String txt, Object... args)	Evident
protected void	hint(Location<XMLDocumentIdentifier> loc, String txt, Object... args)	Evident
(package private) boolean	isDone(Expression exp)	If not yet visited, create the director map objects.
static void	liftFirstsToSeq(Expression exp, Seq ns)	All directors from "exp" are lifted into the directory maps of "ns", to point to the "exp"-expression.
protected void	LL1_violation(String s, Expression from, Expression to)	Signal the fact that a tag is already contained in the domain of the (non-weak) director map.
protected void	makeGenericHints(Module module, List<String> names)	Emit a sequence of hints pointing to the sequence of import commands, when (erroneously) a definition is referred which is marked with "#GENERIC".
protected void	warning(Location<XMLDocumentIdentifier> loc, String txt, Object... args)	Evident

Methods inherited from class eu.bandm.tools.d2d2.base.Navigate.VisitReachable

markToDo, markToDo, process, process, processAll, processPublic

Methods inherited from class eu.bandm.tools.d2d2.model.SinglePhase

action, action, action, action, action, action, action, action, action, action, action, action, action, action, action, action, action, action, action, action, action, action, action, action, action, action, follow_definitions, follow_defInstances, follow_docu, follow_firsts, follow_globalSubsts, follow_imports, follow_itemDocu, follow_localdefs, follow_localSubsts, follow_modules, follow_namespaces, follow_obligates, follow_on, follow_rawModules, follow_text, follow_weakfirsts, follow_xattributes

Methods inherited from class eu.bandm.tools.d2d2.model.MATCH_ONLY_00

_visitor_trace, action, action, action, action, action, compile, followAll_definitions, followAll_defInstances, followAll_docu, followAll_firsts, followAll_globalSubsts, followAll_imports, followAll_itemDocu, followAll_localdefs, followAll_localSubsts, followAll_modules, followAll_namespaces, followAll_obligates, followAll_on, followAll_rawModules, followAll_text, followAll_weakfirsts, followAll_xattributes, foreignObject, match, match, match, match, match, match, match, match, match, match, match, match, match, match, match, match, match, match, match, match, match, match, match, match, match, match, match, match, match, match, match, match, match, match, match, match, match, match, match, match, nomatch

Methods inherited from class java.lang.Object

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

Field Details

msg

protected MessageReceiver<SimpleMessage<XMLDocumentIdentifier>> msg

Evident

currentdef

TagsRegExp currentdef

Required for error diagnosis only.

Constructor Details

FirstCalculator

public FirstCalculator(MessageReceiver<SimpleMessage<XMLDocumentIdentifier>> msg)

Evident

FirstCalculator

public FirstCalculator(MessageReceiver<SimpleMessage<XMLDocumentIdentifier>> msg,
 @Opt
 @Opt ModuleRegistry modreg)

Evident

Parameters:

modreg - ModuleRegistry only needed by "makeGenericHints" for displaying the chain of imported source texts.

Method Details

error

protected void error(Location<XMLDocumentIdentifier> loc,
 String txt,
 Object... args)

Evident

warning

protected void warning(Location<XMLDocumentIdentifier> loc,
 String txt,
 Object... args)

Evident

hint

protected void hint(Location<XMLDocumentIdentifier> loc,
 String txt,
 Object... args)

Evident

action

public void action(TagsRegExp def)

Memorize location (for messages) and descend into the expression.

Overrides:

action in class SinglePhase

action

public void action(CharsRegExp def)

No operation necessary.

Overrides:

action in class SinglePhase

action

public void action(Enumeration def)

No operation necessary.

Overrides:

action in class SinglePhase

isDone

boolean isDone(Expression exp)

If not yet visited, create the director map objects.

Returns:

whether visited before.

action

public void action(Empty x)

Only mark as visited.

Overrides:

action in class SinglePhase

action

public void action(Pcdata x)

Mark as visited and set the director maps.

Overrides:

action in class SinglePhase

action

public void action(Insertion x)

Mark as visited and set the director maps. Insertions can only be in ResolvedModule as synthetic ones, containing only one Reference

Overrides:

action in class SinglePhase

makeGenericHints

protected void makeGenericHints(Module module,
 List<String> names)

Emit a sequence of hints pointing to the sequence of import commands, when (erroneously) a definition is referred which is marked with "#GENERIC".

Parameters:

module - the raw module in which a import statement appears

names - the sequence of identifiers = import keys plus one definition tag

action

public void action(Reference ref)

Put "tag->expr" into the directors map for later parsing. References can refer to Tags, Chars and Enumerations definitions.

Attention: Use the name of the referred declaration object, which is a kind of "d2d-tag" with possibly local scope. Do not use the referring source text, which already has been normalized to module level scope.

Overrides:

action in class SinglePhase

copyMult

protected void copyMult(GrUnary x,
 boolean canEps)

Copy the directors into a compound expression "x" from its component.

action

public void action(Opt x)

Copy the directors into the compound expression "x" from its component.

Overrides:

action in class SinglePhase

action

public void action(Star x)

Copy the directors into the compound expression "x" from its component.

Overrides:

action in class SinglePhase

action

public void action(Plus x)

Copy the directors into the compound expression "x" from its component.

Overrides:

action in class SinglePhase

LL1_violation

protected void LL1_violation(String s,
 Expression from,
 Expression to)

Signal the fact that a tag is already contained in the domain of the (non-weak) director map.

addFromTo

protected void addFromTo(Expression from,
 Expression to,
 boolean isalt)

"From" is the component expression FROM which the director map is copied inTO the map ruling the compond expression called "to".d

action

public void action(Alt alt)

Fill the director maps to the disjunction of all directors of the components.

Overrides:

action in class SinglePhase

action

public void action(Perm x)

Fill the director maps to the disjunction of all directors of the components.

Overrides:

action in class SinglePhase

action

public void action(Seq x)

Fill the director maps of a sequence expression, depending on the possible epsilon-results of its components.

Overrides:

action in class SinglePhase

liftFirstsToSeq

public static void liftFirstsToSeq(Expression exp,
 Seq ns)

All directors from "exp" are lifted into the directory maps of "ns", to point to the "exp"-expression.