public class GrammarParser extends java.lang.Object implements Prototype
Modifier and Type | Field and Description |
---|---|
protected static int |
BOOLEAN_CONSTANT |
protected static int |
COMMENT |
static java.lang.String[] |
DEFAULT_REGEXES
The default regular expressions for tokens in the parser.
|
protected static int |
EQUALS |
protected static int |
FUNCTION |
protected static int |
LPAREN |
protected static int |
NUMERIC_CONSTANT |
static java.lang.String |
P_PARSER |
protected static int |
PIPE |
protected static int |
RPAREN |
protected static int |
RULE |
protected static int |
STRING_CONSTANT |
Constructor and Description |
---|
GrammarParser() |
Modifier and Type | Method and Description |
---|---|
java.lang.Object |
clone()
Creates a new individual cloned from a prototype,
and suitable to begin use in its own evolutionary
context.
|
Parameter |
defaultBase()
Returns the default base for this prototype.
|
void |
enumerateGrammarTree(GrammarNode gn)
Run BFS to enumerate the whole grammar tree into all necessary
indices lists/hash-maps, we *need* to run BFS because the decoding of
the "GE array to tree" works in a BFS fashion, so we need to stick with that;
After enumeration, we will have four data-structures like these --
(1) productionRuleList (a flattened grammar tree):
grammar-tree ==> {rule-0, rule-1, ,,, rule-(n-1)}
(2) ruleToIndex:
rule-0 --> 0
rule-1 --> 1
,
,
rule-(n-1) --> (n-1)
(3) indexToRule (reverse of ruleToIndex):
0 --> rule-0
1 --> rule-1
,
,
n-1 --> rule-(n-1)
and then, last but not the least, the relative rule index --
(4) absIndexToRelIndex:
if we have two rules like " -> |
|
java.util.ArrayList |
gatherFirstSets(GrammarNode gn,
GrammarNode parent)
Generate the FIRST-SET for each production rule and store them in the
global hash-table, this runs a DFS on the grammar tree, the returned ArrayList
is discarded and the FIRST-SETs are organized in a hash-map called
"ruleToFirstSet" as follows --
rule-0 --> {FIRST-SET-0}
rule-1 --> {FIRST-SET-1}
,
,
rule-(n-1) --> {FIRST-SET-(n-1)}
|
java.util.ArrayList |
gatherFollowSets(GrammarNode gn,
GrammarNode parent)
We do not have any example grammar to test with FOLLOW-SETs,
so the FOLLOW-SET is empty, we need to test with a grammar
that contains post-fix notations;
this needs to be implemented properly with a new grammar.
|
void |
gatherPredictSets(GrammarNode gn,
GrammarNode parent)
Populate the PREDICT-SET from the FIRST-SETs and the FOLLOW-SETs,
as we do not have FOLLOW-SET, so FIRST-SET == PREDICT-SET;
this needs to be implemented, when the FOLLOW-SETs are done properly.
|
java.lang.String[] |
getRegexes()
Returns the regular expressions to use for tokenizing these rules.
|
static void |
main(java.lang.String[] args)
A simple testing facility.
|
GrammarRuleNode |
parseRules(EvolutionState state,
java.io.BufferedReader reader,
GPFunctionSet gpfs)
Parses the rules from a grammar and returns the resulting GrammarRuleNode root.
|
void |
populatePredictiveParseTable(GrammarNode gn)
Now populate the predictive-parse table, this procedure reads
hash-maps/tables for the grammar-rule indices, PREDICT-SETs etc,
and assigns the corresponding values in the predictive-parse table.
|
void |
setup(EvolutionState state,
Parameter base)
Sets up the object by reading it from the parameters stored
in state, built off of the parameter base base.
|
java.lang.String |
toString() |
boolean |
validateRules()
Checks that all grammar rules in ruleshashmap have at least one possible production
|
public static final java.lang.String P_PARSER
public static final java.lang.String[] DEFAULT_REGEXES
protected static final int COMMENT
protected static final int LPAREN
protected static final int RPAREN
protected static final int RULE
protected static final int PIPE
protected static final int EQUALS
protected static final int NUMERIC_CONSTANT
protected static final int BOOLEAN_CONSTANT
protected static final int STRING_CONSTANT
protected static final int FUNCTION
public java.lang.String[] getRegexes()
public Parameter defaultBase()
Prototype
defaultBase
in interface Prototype
public void setup(EvolutionState state, Parameter base)
Prototype
For prototypes, setup(...) is typically called once for the prototype instance; cloned instances do not receive the setup(...) call. setup(...) may be called more than once; the only guarantee is that it will get called at least once on an instance or some "parent" object from which it was ultimately cloned.
public java.lang.Object clone()
Prototype
Typically this should be a full "deep" clone. However, you may share certain elements with other objects rather than clone hem, depending on the situation:
Implementations.
public Object clone()
{
try
{
return super.clone();
}
catch ((CloneNotSupportedException e)
{ throw new InternalError(); } // never happens
}
public Object clone()
{
try
{
MyObject myobj = (MyObject) (super.clone());
// put your deep-cloning code here...
}
catch ((CloneNotSupportedException e)
{ throw new InternalError(); } // never happens
return myobj;
}
public Object clone()
{
MyObject myobj = (MyObject) (super.clone());
// put your deep-cloning code here...
return myobj;
}
public GrammarRuleNode parseRules(EvolutionState state, java.io.BufferedReader reader, GPFunctionSet gpfs)
public java.lang.String toString()
toString
in class java.lang.Object
public boolean validateRules()
public void enumerateGrammarTree(GrammarNode gn)
public java.util.ArrayList gatherFirstSets(GrammarNode gn, GrammarNode parent)
public java.util.ArrayList gatherFollowSets(GrammarNode gn, GrammarNode parent)
public void gatherPredictSets(GrammarNode gn, GrammarNode parent)
public void populatePredictiveParseTable(GrammarNode gn)
public static void main(java.lang.String[] args) throws java.io.FileNotFoundException
java.io.FileNotFoundException