example_text_pattern

Regular expressions for Gleam on Erlang and Geam.

Erlang uses the included OTP re implementation with unicode and ucp. Geam uses the geam-example-text-pattern Rust provider and its regex engine. Pattern syntax, replacement syntax, zero-length matches, resource limits, and error messages follow each engine. There is no JavaScript implementation.

Types

CompileError

An invalid regular expression, with a message from the active regex engine.

pub type CompileError {
  CompileError(message: String)
}

Constructors

```
CompileError(message: String)
```

Pattern

A compiled regular expression, opaque to Gleam.

Equality and inspection are runtime-specific, not portable guarantees. On Geam, identical source text compares equal and inspection displays the pattern text, for example Pattern("[A-Za-z]+"). On Erlang, this is OTP’s opaque compiled pattern.

pub type Pattern

Values

compile

pub fn compile(source: String) -> Result(Pattern, CompileError)

Compile a regular expression, or return Error(CompileError(message)) if the pattern is invalid. Syntax is interpreted by the active engine without translation; a pattern accepted by one engine may be rejected by the other.

find_all

pub fn find_all(pattern: Pattern, text: String) -> List(String)

Return whole, non-overlapping matches from left to right, or an empty list if there are no matches. Capturing groups are not returned separately. Zero-length matches follow the active engine’s iteration rules.

is_match

pub fn is_match(pattern: Pattern, text: String) -> Bool

Check whether any part of text matches the pattern. The pattern is not automatically anchored to the start or end of the text.

replace_all

pub fn replace_all(
  pattern: Pattern,
  text: String,
  replacement: String,
) -> String

Replace every non-overlapping match with replacement. Replacement syntax follows the active engine. Geam uses $0 for the whole match and $1 for the first capture. Erlang uses & and \\1 respectively (the latter written with an escaped backslash in a Gleam string).