release 6.6.1

• Fix definition of \X

release 6.6.0

• NEW: ASCII only mode options for character type/property (?WDSP)
• NEW: Extended Grapheme Cluster boundary \y, \Y (*original)
• NEW: Extended Grapheme Cluster \X
• Range-clear (Absent-clear) operator restores previous range in backtrack.

release 6.5.0

• NEW: \K (keep)
• NEW: \R (general newline) \N (no newline)
• NEW: \O (true anychar)
• NEW: if-then-else syntax (?(...)...|...)
• NEW: Backreference validity checker (*original)
• NEW: Absent repeater (?~absent)
• NEW: Absent expression (?~|absent|expr) (*original)
• NEW: Absent range cutter (?~|absent) (*original)

release 6.4.0

• Fix fatal problem of endless repeat on Windows
• NEW: call zero (call the total regexp)
• NEW: relative backref and relative call by positive number

release 6.3.0

NEW SYNTAX: escape-o-brace for octal codepoint.
Fix many bugs: #55 - #60

release 6.2.0

Fix many bugs. (#52 etc..)

NEW API: onig_set_capture_num_limit() (#46)

release 5.9.6_p1

Fix Issue #35

release 6.1.3

Fix Issue #35

release 6.1.2

• allow word bound, word begin and word end in look-behind.
• NEW option: ONIG_OPTION_CHECK_VALIDITY_OF_STRING

release 6.1.1

• Fix fatal bug Issue #23