edu.vub.at.objects.natives.grammar
Class AGSymbol

java.lang.Object
  edu.vub.at.objects.natives.NATNil
      edu.vub.at.objects.natives.NATByCopy
          edu.vub.at.objects.natives.grammar.NATAbstractGrammar
              edu.vub.at.objects.natives.grammar.AGExpression
                  edu.vub.at.objects.natives.grammar.AGSymbol

All Implemented Interfaces:

ATAbstractGrammar, ATConversions, ATExpression, ATNil, ATObject, ATStatement, ATSymbol, java.io.Serializable

Direct Known Subclasses:

AGSelf

public class AGSymbol

extends AGExpression

implements ATSymbol

Author:

tvcutsem The native implementation of a symbol AG element. Symbols should only be created via a call to AGSymbol.alloc This ensures that symbols remain unique within one AmbientTalk VM.

See Also:

Serialized Form

Field Summary

private static java.util.HashMap	_STRINGPOOL_ hashmap shared by ALL actors/VMs, hence, thread access should be explicitly synchronized
private java.lang.String	txt_

Fields inherited from class edu.vub.at.objects.natives.NATNil

_INSTANCE_

Constructor Summary

protected

AGSymbol(java.lang.String txt)

Method Summary

static AGSymbol	alloc(NATText txt)
ATTable	base__opmns__opgtx_(ATObject obj) Used during import: declarations to conveniently denote aliases for names.
ATSymbol	base_asSymbol()
ATText	base_getText() Transform a symbol into a string.
boolean	base_isSymbol()
boolean	equals(java.lang.Object other) By default, two AmbientTalk objects are equal if they are the same object, or one is a proxy for the same object.
int	hashCode()
static AGSymbol	jAlloc(java.lang.String name)
ATObject	meta_eval(ATContext ctx) To evaluate a symbol reference, look up the symbol in the lexical scope.
NATText	meta_print() Prints out the object in a human-readable way.
ATObject	meta_quote(ATContext ctx) Quoting a symbol results in the same symbol.
ATObject	meta_resolve() After deserialization, ensure that the symbol remains unique.
java.lang.String	toString()

Methods inherited from class edu.vub.at.objects.natives.grammar.AGExpression

base_asExpression, meta_getStripes

Methods inherited from class edu.vub.at.objects.natives.NATByCopy

meta_pass

Methods inherited from class edu.vub.at.objects.natives.NATNil

asAmbientTalkObject, asJavaClassUnderSymbiosis, asJavaObjectUnderSymbiosis, asNativeBoolean, asNativeException, asNativeFarReference, asNativeFraction, asNativeNumber, asNativeNumeric, asNativeTable, asNativeText, base__opeql__opeql_, base_asActorMirror, base_asAsyncMessage, base_asBegin, base_asBoolean, base_asClosure, base_asDefinition, base_asFarReference, base_asField, base_asHandler, base_asMessage, base_asMessageCreation, base_asMethod, base_asMirror, base_asNumber, base_asSplice, base_asStatement, base_asStripe, base_asTable, base_asUnquoteSplice, base_asVariableAssignment, base_init, base_isBoolean, base_isCallFrame, base_isClosure, base_isFarReference, base_isMessageCreation, base_isMethod, base_isMirror, base_isSplice, base_isStripe, base_isTable, base_isUnquoteSplice, base_isVariableAssignment, base_new, createChild, isAmbientTalkObject, isJavaObjectUnderSymbiosis, isNativeBoolean, isNativeField, isNativeText, meta_addField, meta_addMethod, meta_assignField, meta_assignVariable, meta_clone, meta_defineField, meta_doesNotUnderstand, meta_extend, meta_getDynamicParent, meta_getLexicalParent, meta_grabField, meta_grabMethod, meta_invoke, meta_isCloneOf, meta_isRelatedTo, meta_isStripedWith, meta_listFields, meta_listMethods, meta_lookup, meta_newInstance, meta_receive, meta_respondsTo, meta_select, meta_send, meta_share, readResolve, writeReplace

Methods inherited from class java.lang.Object

clone, finalize, getClass, notify, notifyAll, wait, wait, wait

Methods inherited from interface edu.vub.at.objects.ATObject

base__opeql__opeql_, base_init, base_new, meta_addField, meta_addMethod, meta_assignField, meta_assignVariable, meta_clone, meta_defineField, meta_doesNotUnderstand, meta_extend, meta_getDynamicParent, meta_getLexicalParent, meta_getStripes, meta_grabField, meta_grabMethod, meta_invoke, meta_isCloneOf, meta_isRelatedTo, meta_isStripedWith, meta_listFields, meta_listMethods, meta_lookup, meta_newInstance, meta_pass, meta_receive, meta_respondsTo, meta_select, meta_send, meta_share

Methods inherited from interface edu.vub.at.objects.coercion.ATConversions

asAmbientTalkObject, asJavaClassUnderSymbiosis, asJavaObjectUnderSymbiosis, asNativeBoolean, asNativeException, asNativeFarReference, asNativeFraction, asNativeNumber, asNativeNumeric, asNativeTable, asNativeText, base_asActorMirror, base_asAsyncMessage, base_asBegin, base_asBoolean, base_asClosure, base_asDefinition, base_asExpression, base_asFarReference, base_asField, base_asHandler, base_asMessage, base_asMessageCreation, base_asMethod, base_asMirror, base_asNumber, base_asSplice, base_asStatement, base_asStripe, base_asTable, base_asUnquoteSplice, base_asVariableAssignment, base_isBoolean, base_isCallFrame, base_isClosure, base_isFarReference, base_isMessageCreation, base_isMethod, base_isMirror, base_isSplice, base_isStripe, base_isTable, base_isUnquoteSplice, base_isVariableAssignment, isAmbientTalkObject, isJavaObjectUnderSymbiosis, isNativeBoolean, isNativeField, isNativeText

Field Detail

_STRINGPOOL_

private static final java.util.HashMap _STRINGPOOL_

hashmap shared by ALL actors/VMs, hence, thread access should be explicitly synchronized

txt_

private final java.lang.String txt_

Constructor Detail

AGSymbol

protected AGSymbol(java.lang.String txt)

Method Detail

jAlloc

public static final AGSymbol jAlloc(java.lang.String name)

alloc

public static final AGSymbol alloc(NATText txt)

base_getText

public ATText base_getText()

Description copied from interface: ATSymbol

Transform a symbol into a string.

Specified by:

base_getText in interface ATSymbol

base__opmns__opgtx_

public ATTable base__opmns__opgtx_(ATObject obj)
                            throws InterpreterException

Description copied from interface: ATSymbol

Used during import: declarations to conveniently denote aliases for names. `a -> `b is equivalent to [ `a, `b ]

Specified by:

base__opmns__opgtx_ in interface ATSymbol

Throws:

InterpreterException

meta_eval

public ATObject meta_eval(ATContext ctx)
                   throws InterpreterException

To evaluate a symbol reference, look up the symbol in the lexical scope. AGSYM(txt).eval(ctx) = ctx.scope.lookup(AGSYM(txt))

Specified by:

meta_eval in interface ATObject

Overrides:

meta_eval in class NATNil

Returns:

the value bound to this symbol in the lexical environment

Throws:

InterpreterException

meta_quote

public ATObject meta_quote(ATContext ctx)
                    throws InterpreterException

Quoting a symbol results in the same symbol. sym.quote(ctx) = sym

Specified by:

meta_quote in interface ATObject

Overrides:

meta_quote in class NATNil

Throws:

InterpreterException

meta_print

public NATText meta_print()
                   throws InterpreterException

Description copied from interface: ATObject

Prints out the object in a human-readable way.

Specified by:

meta_print in interface ATObject

Overrides:

meta_print in class NATNil

Throws:

InterpreterException

base_isSymbol

public boolean base_isSymbol()

Specified by:

base_isSymbol in interface ATConversions

Overrides:

base_isSymbol in class NATNil

base_asSymbol

public ATSymbol base_asSymbol()

Specified by:

base_asSymbol in interface ATConversions

Overrides:

base_asSymbol in class NATNil

equals

public boolean equals(java.lang.Object other)

Description copied from class: NATNil

By default, two AmbientTalk objects are equal if they are the same object, or one is a proxy for the same object.

Overrides:

equals in class NATNil

hashCode

public int hashCode()

toString

public java.lang.String toString()

Overrides:

toString in class NATNil

meta_resolve

public ATObject meta_resolve()
                      throws InterpreterException

After deserialization, ensure that the symbol remains unique.

Specified by:

meta_resolve in interface ATObject

Overrides:

meta_resolve in class NATByCopy

Throws:

InterpreterException