regex
(see blob/2). Defined Options
are given below. Please consult the PCRE2
API documentation for details. If an option is repeated, the first
value is used and subsequent values are ignored. Unrecognized options
are ignored. Unless otherwise specified, boolean options default to false
.
Some options may not exist on your system, depending on the PCRE2
version and how it was built - these unsupported options are silently
ignored.
The various matching predicates can take either a Regex blob or a string pattern; if they are given a string pattern, they call re_compile/3 and cache the result; so, there is little reason to use re_compile/3 directly.
anchored(Bool)
Iftrue
, match only at the first positionauto_capture(Bool)
Enable use of numbered capturing parentheses. (defaulttrue
)bsr(Mode)
Ifanycrlf
,\
R only matches CR, LF or CRLF; ifunicode
,\
R matches all Unicode line endings.bsr2(Mode)
- synonym forbsr(Mode)
.caseless(Bool)
Iftrue
, do caseless matching.compat(With)
Error - PCRE1 hadcompat(javascript)
for JavaScript compatibility, but PCRE2 has removed that.dollar_endonly(Bool)
Iftrue
, $ not to match newline at enddotall(Bool)
Iftrue
, . matches anything including NLdupnames(Bool)
Iftrue
, allow duplicate names for subpatternsextended(Bool)
Iftrue
, ignore white space and # commentsfirstline(Bool)
Iftrue
, force matching to be before newlinegreedy(Bool)
Iftrue
, operators such as+
and*
are greedy unless followed by?
; iffalse
, the operators are not greedy and?
has the opposite meaning. It can also beset by a‘(?U)` within the pattern - see the PCRE2 pattern internal option setting documentation for details and note that the PCRE2 option is UNGREEDY, which is the inverse of this packagesgreedy
options. (defaulttrue
)compat(With)
Raises an errr - PCRE1 hadcompat(javascript)
for JavaScript compatibility, but PCRE2 has removed that option . Consider using thealt_bsux
andextra_alt_bsux
options.multiline(Bool)
Iftrue
,^
and $ match newlines within datanewline(Mode)
Ifany
, recognize any Unicode newline sequence; ifanycrlf
(default), recognize CR, LF, and CRLF as newline sequences; ifcr
, recognize CR; iflf
, recognize LF;crlf
recognize CRLF as newline; ifnul
, recognize the NULL character (0x00) as newline.newline2(Mode)
- synonym fornewline(Mode)
.ucp(Bool)
Iftrue
, use Unicode properties for\
d,\
w, etc.utf_check(Bool)
- see PCRE2 API documentation You should not need this because SWI-Prolog ensures that the UTF8 strings are valid,endanchored(boolean)
- see PCRE2 API documentationallow_empty_class(boolean)
- see PCRE2 API documentationalt_bsux(boolean)
- see PCRE2 API documentationauto_callout(boolean)
- see PCRE2 API documentationmatch_unset_backref(boolean)
- see PCRE2 API documentationnever_ucp(boolean)
- see PCRE2 API documentationnever_utf(boolean)
- see PCRE2 API documentationauto_possess(boolean)
- see PCRE2 API documentation (defaulttrue
)dotstar_anchor(boolean)
- see PCRE2 API documentation (defaulttrue
)start_optimize(boolean)
- see PCRE2 API documentation (defaulttrue
)utf(boolean)
- see PCRE2 API documentationnever_backslash_c(boolean)
- see PCRE2 API documentationalt_circumflex(boolean)
- see PCRE2 API documentationalt_verbnames(boolean)
- see PCRE2 API documentationuse_offset_limit(boolean)
- see PCRE2 API documentationextended_more(boolean)
- see PCRE2 API documentationliteral(boolean)
- see PCRE2 API documentationmatch_invalid_utf(boolean)
- see PCRE2 API documentationjit_complete(boolean)
- see PCRE2 API documentationjit_partial_soft(boolean)
- see PCRE2 API documentationjit_partial_hard(boolean)
- see PCRE2 API documentationjit_invalid_utf(boolean)
- see PCRE2 API documentationjit(boolean)
- see PCRE2 API documentation (defaulttrue
)copy_matched_subject(boolean)
- see PCRE2 API documentation
In addition to the options above that directly map to PCRE flags the following options are processed:
optimise(Bool)
oroptimize(Bool)
Turns on the JIT compiler for additional optimization that greatly that speeds up the matching performance of many patterns. (Note that he meaning has changed slightly from the PCRE1 implementation- PCRE2 always optimises where possible; this is an additional optimisation.)
capture_type(+Type)
How to return the matched part of the input and possibly captured groups in there. Possible values are:- string
- Return the captured string as a string (default).
- atom
- Return the captured string as an atom.
- range
- Return the captured string as a pair
Start-Length
. Note that we useStart-Length
rather than the more conventionalStart-End
to allow for immediate use with sub_atom/5 and sub_string/5. - term
- Parse the captured string as a Prolog term. This is notably practical if you capture a number.
The capture_type
specifies the default for this pattern.
The interface supports a different type for each named group
using the syntax‘(?<name_T>...)`,
where T is one of S
(string),
A
(atom), I
(integer), F
(float), N
(number), T
(term) and R
(range). In the
current implementation I
,
F
and N
are synonyms for T
.
Future versions may act different if the parsed value is not of the
requested numeric type.
Note that re_compile/3 does not support the Pattern/Flags form that is supported by re_match/3, re_replace/4, etc.; the Pattern must be text and all compile options specified in Options.