com.oracle.truffle.regex.tregex.matchers

Class RangeTreeMatcher

java.lang.Object

com.oracle.truffle.regex.tregex.matchers.CharMatcher

com.oracle.truffle.regex.tregex.matchers.InvertibleCharMatcher

com.oracle.truffle.regex.tregex.matchers.RangeTreeMatcher

public final class RangeTreeMatcher
extends InvertibleCharMatcher

Character range matcher that compiles to a static binary search. Example:
Given a list of ranges [[1, 2], [4, 5], [10, 11], [20, 22]], this matcher will compile to something similar to this:

 match(char c) {
     if (c < 4) {
         return 1 <= c && c <= 2;
     } else if (c > 5) {
         if (c < 10) {
             return false;
         } else if (c > 11) {
             return 20 <= c && c <= 22;
         } else {
             return true;
         }
     } else {
         return true;
     }
 }
 

Method Summary

Modifier and Type	Method and Description
static RangeTreeMatcher	create(boolean invert, int[] ranges) Constructs a new RangeTreeMatcher.
int	estimatedCost() Conservatively estimate the equivalent number of integer comparisons of calling CharMatcher.match(int).
boolean	match(int c) Check if a given code point matches this CharMatcher.
String	toString()

Methods inherited from class com.oracle.truffle.regex.tregex.matchers.InvertibleCharMatcher

modifiersToString, result, result

Methods inherited from class java.lang.Object

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

Method Detail

create

public static RangeTreeMatcher create(boolean invert,
                                      int[] ranges)

Constructs a new RangeTreeMatcher.

Parameters:

invert - see InvertibleCharMatcher.

ranges - a sorted array of character ranges in the form [lower inclusive bound of range 0, higher inclusive bound of range 0, lower inclusive bound of range 1, higher inclusive bound of range 1, ...]. The array contents are not modified by this method.

Returns:

a new RangeTreeMatcher.

match

public boolean match(int c)

Description copied from class: CharMatcher

Check if a given code point matches this CharMatcher.

Specified by:

match in class CharMatcher

Parameters:

c - any code point.

Returns:

true if the character matches.

See Also:

CompilerDirectives.isPartialEvaluationConstant(Object)

estimatedCost

public int estimatedCost()

Description copied from class: CharMatcher

Conservatively estimate the equivalent number of integer comparisons of calling CharMatcher.match(int).

Specified by:

estimatedCost in class CharMatcher

Returns:

the number of integer comparisons one call to CharMatcher.match(int) is roughly equivalent to. Array loads are treated as two comparisons.

toString

public String toString()

Overrides:

toString in class Object