join / split / words / first

Convert between strings and lists, and pluck the first matching element.

These routines bridge strings and lists: split and words break a string apart, join puts a list back together, and first returns the earliest element matching a test.

join and split #

join glues a list into a string with a separator; split is the inverse.

say <a b c>.join("-");
say "a,b,c".split(",");

a-b-c
(a b c)

words #

words splits on runs of whitespace, ignoring leading and trailing space — the right tool for tokenising text.

say "the quick fox".words;

(the quick fox)

first #

first returns the earliest element for which the block is true (not the index).

say (1..10).first(* > 4);

5

Notes #

• split returns a Seq; join always returns a Str. split can also take a regex, and :skip-empty drops empty fields.
• words is roughly split(/\s+/) with the empty edges removed; use it in preference when you just want the non-space chunks.
• Related pluckers: first (element), first(:k, …) (its key/index), and grep (all matches instead of just the first).