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Updated documentation

This commit is contained in:
Sam Harwell 2012-12-07 08:51:10 -06:00
parent 38b5a8321b
commit 26f16bed73
1 changed files with 61 additions and 42 deletions
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103
tool/src/org/antlr/v4/automata/ParserATNFactory.java
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@ -159,7 +159,7 @@ public class ParserATNFactory implements ATNFactory {
return h;
}
/** From label A build Graph o-A->o */
/** From label {@code A} build graph {@code o-A->o}. */
@Override
public Handle tokenRef(TerminalAST node) {
ATNState left = newState(node);
@ -170,9 +170,9 @@ public class ParserATNFactory implements ATNFactory {
return new Handle(left, right);
}
/** From set build single edge graph o->o-set->o. To conform to
/** From set build single edge graph {@code o->o-set->o}. To conform to
* what an alt block looks like, must have extra state on left.
* This handles ~A also, converted to ~{A} set.
* This also handles {@code ~A}, converted to {@code ~{A}} set.
*/
@Override
public Handle set(GrammarAST associatedAST, List<GrammarAST> terminals, boolean invert) {
@ -193,7 +193,7 @@ public class ParserATNFactory implements ATNFactory {
return new Handle(left, right);
}
/** Not valid for non-lexers */
/** Not valid for non-lexers. */
@Override
public Handle range(GrammarAST a, GrammarAST b) {
throw new UnsupportedOperationException();
@ -216,18 +216,22 @@ public class ParserATNFactory implements ATNFactory {
return tokenRef(stringLiteralAST);
}
/** [Aa] char sets not allowed in parser */
/** {@code [Aa]} char sets not allowed in parser */
@Override
public Handle charSetLiteral(GrammarAST charSetAST) {
return null;
}
/** For reference to rule r, build
/**
* For reference to rule {@code r}, build
*
* <pre>
* o->(r) o
* </pre>
*
* where (r) is the start of rule r and the trailing o is not linked
* to from rule ref state directly (uses followState).
* where {@code (r)} is the start of rule {@code r} and the trailing
* {@code o} is not linked to from rule ref state directly (uses
* {@link RuleTransition#followState}).
*/
@Override
public Handle ruleRef(GrammarAST node) {
@ -258,7 +262,7 @@ public class ParserATNFactory implements ATNFactory {
epsilon(stop, right);
}
/** From an empty alternative build o-e->o */
/** From an empty alternative build {@code o-e->o}. */
@Override
public Handle epsilon(GrammarAST node) {
ATNState left = newState(node);
@ -269,8 +273,8 @@ public class ParserATNFactory implements ATNFactory {
}
/** Build what amounts to an epsilon transition with a semantic
* predicate action. The pred is a pointer into the AST of
* the SEMPRED token.
* predicate action. The {@code pred} is a pointer into the AST of
* the {@link ANTLRParser#SEMPRED} token.
*/
@Override
public Handle sempred(PredAST pred) {
@ -286,7 +290,7 @@ public class ParserATNFactory implements ATNFactory {
/** Build what amounts to an epsilon transition with an action.
* The action goes into ATN though it is ignored during prediction
* if actionIndex &lt; 0. Only forced are executed during prediction.
* if {@link ActionTransition#actionIndex actionIndex}{@code <0}.
*/
@Override
public Handle action(ActionAST action) {
@ -304,26 +308,29 @@ public class ParserATNFactory implements ATNFactory {
return null;
}
/** From A|B|..|Z alternative block build
*
* o->o-A->o->o (last ATNState is BlockEndState pointed to by all alts)
* | ^
* |->o-B->o--|
* | |
* ... |
* | |
* |->o-Z->o--|
*
* So start node points at every alternative with epsilon transition
* and every alt right side points at a block end ATNState.
/**
* From {@code A|B|..|Z} alternative block build
*
* Special case: only one alternative: don't make a block with alt
* begin/end.
* <pre>
* o->o-A->o->o (last ATNState is BlockEndState pointed to by all alts)
* | ^
* |->o-B->o--|
* | |
* ... |
* | |
* |->o-Z->o--|
* </pre>
*
* Special case: if just a list of tokens/chars/sets, then collapse
* to a single edged o-set->o graph.
*
* TODO: Set alt number (1..n) in the states?
* So start node points at every alternative with epsilon transition and
* every alt right side points at a block end ATNState.
* <p/>
* Special case: only one alternative: don't make a block with alt
* begin/end.
* <p/>
* Special case: if just a list of tokens/chars/sets, then collapse to a
* single edged o-set->o graph.
* <p/>
* TODO: Set alt number (1..n) in the states?
*/
@Override
public Handle block(BlockAST blkAST, GrammarAST ebnfRoot, List<Handle> alts) {
@ -413,13 +420,17 @@ public class ParserATNFactory implements ATNFactory {
return new Handle(first.left, last.right);
}
/** From (A)? build either:
/**
* From {@code (A)?} build either:
*
* <pre>
* o--A->o
* | ^
* o---->|
* </pre>
*
* or, if A is a block, just add an empty alt to the end of the block
* or, if {@code A} is a block, just add an empty alt to the end of the
* block
*/
@NotNull
@Override
@ -439,14 +450,17 @@ public class ParserATNFactory implements ATNFactory {
return blk;
}
/** From (blk)+ build
/**
* From {@code (blk)+} build
*
* <pre>
* |---------|
* v |
* [o-blk-o]->o->o
* </pre>
*
* We add a decision for loop back node to the existing one at
* blk start.
* We add a decision for loop back node to the existing one at {@code blk}
* start.
*/
@NotNull
@Override
@ -482,17 +496,20 @@ public class ParserATNFactory implements ATNFactory {
return new Handle(blkStart, end);
}
/** From (blk)* build ( blk+ )? with *two* decisions, one for entry
* and one for choosing alts of blk.
/**
* From {@code (blk)*} build {@code ( blk+ )?} with *two* decisions, one for
* entry and one for choosing alts of {@code blk}.
*
* <pre>
* |-------------|
* v |
* o--[o-blk-o]->o o
* | ^
* -----------------|
* </pre>
*
* Note that the optional bypass must jump outside the loop as (A|B)* is
* not the same thing as (A|B|)+.
* Note that the optional bypass must jump outside the loop as
* {@code (A|B)*} is not the same thing as {@code (A|B|)+}.
*/
@NotNull
@Override
@ -529,7 +546,7 @@ public class ParserATNFactory implements ATNFactory {
return new Handle(entry, end);
}
/** Build an atom with all possible values in its label */
/** Build an atom with all possible values in its label. */
@NotNull
@Override
public Handle wildcard(GrammarAST node) {
@ -573,7 +590,7 @@ public class ParserATNFactory implements ATNFactory {
}
}
/** add an EOF transition to any rule end ATNState that points to nothing
/** Add an EOF transition to any rule end ATNState that points to nothing
* (i.e., for all those rules not invoked by another rule). These
* are start symbols then.
*
@ -641,7 +658,9 @@ public class ParserATNFactory implements ATNFactory {
return false;
}
// (BLOCK (ALT .)) or (BLOCK (ALT 'a') (ALT .))
/**
* {@code (BLOCK (ALT .))} or {@code (BLOCK (ALT 'a') (ALT .))}.
*/
public static boolean blockHasWildcardAlt(@NotNull GrammarAST block) {
for (Object alt : block.getChildren()) {
if ( !(alt instanceof AltAST) ) continue;