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when/  string
unless/  string

2.4 Strings🔗

 (require toolbox/string) package: toolbox-lib

syntax

(when/string test-expr body ...+)

Equivalent to (if test-expr (let () body ...) ""), except that the last body form must evaluate to a string, or an exn:fail:contract exception is raised.

syntax

(unless/string test-expr body ...+)

Equivalent to (if test-expr "" (let () body ...)), except that the last body form must evaluate to a string, or an exn:fail:contract exception is raised.