org.erights.e.elang.evm
Class Pattern

java.lang.Object
  |
  +--org.erights.e.elang.evm.ParseNode
        |
        +--org.erights.e.elang.evm.ENode
              |
              +--org.erights.e.elang.evm.Pattern

All Implemented Interfaces:

Cloneable, EPrintable, MatchMaker

Direct Known Subclasses:

CdrPattern, IgnorePattern, ListPattern, NounPattern, QuasiLiteralPatt, QuasiPatternPatt, SuchThatPattern

public abstract class Pattern

extends ENode

Untamed: A Pattern 1) "evaluates" in a scope, 2) matches some specimen object, 3) binding names in this scope to values derived (usually extracted) from the specimen, and 4) returns whether the match was successful.

Author:

Mark S. Miller

Field Summary

Fields inherited from class org.erights.e.elang.evm.ENode

Fields inherited from class org.erights.e.elang.evm.ParseNode

NUM_PR, PR_ASSIGN, PR_CALL, PR_COMP, PR_EEXPR, PR_LISTPATT, PR_ORDER, PR_PATTERN, PR_PRIM, PR_START

Constructor Summary

(package private)

Pattern(SourceSpan optSpan)

Method Summary

void	__printOn(TextWriter out) Enabled: @see #subPrintOn
abstract String	optName() Enabled: If this pattern is the binding occurence of a name, and it would bind the name to a coercion of the specimen as a whole, return the name.
Pattern	substitute(ConstList args) Enabled:
(package private) abstract void	testMatch(EvalContext ctx, Object specimen, OneArgFunc optEjector) If this pattern matches the specimen, add macthing bindings to the scope.

Methods inherited from class org.erights.e.elang.evm.ENode

cleanCopy, computeStaticScope, copy, getOptPatternMap, getOptScopeMap, getPatternMap, getScopeMap, qbuild, setPatternMap, setScopeMap, staticScope, synEnv, welcome

Methods inherited from class org.erights.e.elang.evm.ParseNode

asText, getOptSpan, lnPrintOn, lnPrintOn, matchBind, matchBind, matchBind, matchBind, printListOn, subPrintOn, toString

Methods inherited from class java.lang.Object

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

Constructor Detail

Pattern

Pattern(SourceSpan optSpan)

Method Detail

__printOn

public void __printOn(TextWriter out)
               throws IOException

Enabled: @see #subPrintOn

Specified by:

__printOn in interface EPrintable

Overrides:

__printOn in class ParseNode

IOException

See Also:

ParseNode.subPrintOn(org.erights.e.elib.oldeio.TextWriter, int)

substitute

public Pattern substitute(ConstList args)

Enabled:

testMatch

abstract void testMatch(EvalContext ctx,
                        Object specimen,
                        OneArgFunc optEjector)

If this pattern matches the specimen, add macthing bindings to the scope.

Otherwise report the reason why not according to optEjector.

optName

public abstract String optName()

Enabled: If this pattern is the binding occurence of a name, and it would bind the name to a coercion of the specimen as a whole, return the name.

Else return null. The purpose is to support the extraction of fully qualified names for object-definition expressions