Regex

matchRE, findRE, replaceRE for pattern-based string operations.

Regex builtins use Java’s java.util.regex.Pattern syntax (the same flavor as Scala’s Regex).

Function	Arity	What
`matchRE`	2	`matchRE s pattern` — true if the entire string matches
`findRE`	2	`findRE s pattern` — first match’s groups (a list); empty list when no match
`findAllRE`	2	`findAllRE s pattern` — list of group-lists, one per match
`replaceRE`	3	`replaceRE s pattern replacement` — every match replaced; `$1`, `$2`, `$0` work in `replacement`
`splitRE`	2	`splitRE s pattern` — split on every match, returning the in-between pieces

Examples

Validate

{{ if matchRE .email '^[^@]+@[^@]+\.[^@]+$' }}
  valid
{{ else }}
  invalid
{{ end }}

Extract groups

{{ ymd := findRE .date '^(\d{4})-(\d{2})-(\d{2})$' }}
{{ // ymd is a list: [whole-match, year, month, day] }}
{{ if ymd | nonEmpty }}
  year = {{ ymd[1] }}, month = {{ ymd[2] }}, day = {{ ymd[3] }}
{{ end }}

The capture-group behavior was restored in 0.2.3 — earlier 0.2.x lost groups.

Find every match

{{ for m <- findAllRE .body '\\[\\[([^\\]]+)\\]\\]' }}
  {{ m[1] }}        // each capture group's text
{{ end }}

Replace

{{ replaceRE .body '\\b(\\w+) - (\\w+)\\b' '$1 — $2' }}

Split

{{ for chunk <- splitRE .text '\\s+' }}
  {{ chunk }}
{{ end }}