Templates

template groups(self: RegExp; input: cstring; groups: varargs[cstring])

Named capture groups. Similar to var [a, b, c] = regex.exec(input).slice(1); in JavaScript.

Example:

import std/jsre
const isoRe = "([2000-2021]{4})-([01-12]{2})-([01-31]{2})T([00-59]{2}):([00-59]{2}):([00-59]{2})".cstring

block:
  let rex = newRegExp(isoRe)
  var year, month, day, hour, minute, second: cstring
  rex.groups "2021-02-31T12:59:30.666", year, month, day, hour, minute, second
  assert year == "2021" and month == "02" and day == "31"
  assert hour == "12" and minute == "59" and second == "30"

block:
  let rex = newRegExp(isoRe)
  var year, month, day, hour, minute, second: cstring
  # "second" is missing, no bug, no index error.
  rex.groups "2021-02-31T12:59:30.666", year, month, day, hour, minute
  assert year == "2021" and month == "02" and day == "31"
  assert hour == "12" and minute == "59"
  assert second  == cstring.default

block:
  let rex = newRegExp(isoRe)
  var year, month, day, hour, minute, second, offByOne: cstring
  # "offByOne" is an extra argument, no bug, no index error.
  rex.groups "2021-02-31T12:59:30.666", year, month, day, hour, minute, second, offByOne
  assert offByOne == cstring.default