SWI-Prolog -- re

Documentation
- Reference manual
- Packages
  - SWI-Prolog Regular Expression library
    - library(pcre): Perl compatible regular expression matching for SWI-Prolog

Availability::- use_module(library(pcre)).(can be autoloaded)

[det]re_replace(+Pattern, +With, +String, -NewString)

[det]re_replace(+Pattern, +With, +String, -NewString, +Options)

Replace matches of the regular expression Pattern in String with With (possibly containing references to captured substrings).

Throws an error if With uses a name that doesn't exist in the Pattern.

Pattern

is the pattern text, optionally followed by /Flags. Flags may include g, replacing all occurences of Pattern. In addition, similar to re_matchsub/4, the final output type can be controlled by a flag a (atom) or s (string, default). The output type can also be specified by the capture_type option. Capture type suffixes can modify behavior; for example, the following will change an ISO 8601 format date (YYYY-MM-DD) to American style (m/d/y), and also remove leading zeros by using the _I suffix:

re_replace("(?<date> (?<year_I>(?:\\d\\d)?\\d\\d) -
            (?<month_I>\\d\\d) - (?<day_I>\\d\\d) )"/x,
           "$month-$day-$year",
           ISODate, AmericanDate)`

With is the replacement text. It may reference captured substrings using \N or $Name. Both N and Name may be written as {N} and {Name} to avoid ambiguities. If a substring is named, it cannot be referenced by its number. The single chracters $ and \ can be escaped by doubling (e.g., re_replace(".","$$","abc",Replaced) results in Replaced="$bc"). (Because \ is an escape character inside strings, you need to write "\\\\" to get a single backslash.)

Options

See re_match/3 for the set of options.

The options that are derived from flags take precedence over the options in the Options list. In the case of conflicting flags, the first one is used (e.g., as results in capture_type(string)). If a capture_type is meaningless (range or term), it is ignored.