string-ci=?(3scm)

hey bestie!! welcome to the string-ci=?(3scm) page — it's from the Scheme Programmer's Manual, and it's serving case-insensitive string comparison realness. no cap, these are the little comparison besties you call when you want string=? vibes but with case folded away 💅

💖 NAME 💖

string-ci=?, string-ci<?, string-ci>?, string-ci<=?, string-ci>=? — case-insensitive string comparison. that's the whole squad, periodt.

📚 LIBRARY 📚

import these bad boys depending on your flavor:

(import (rnrs))                     ;R6RS
(import (rnrs unicode))             ;R6RS
(import (scheme r5rs))              ;R7RS
(import (scheme char))              ;R7RS

✨ SYNOPSIS ✨

the call shapes are literally:

(string-ci=? string1 string2 string3 ...)
(string-ci<? string1 string2 string3 ...)
(string-ci>? string1 string2 string3 ...)
(string-ci<=? string1 string2 string3 ...)
(string-ci>=? string1 string2 string3 ...)

🌸 DESCRIPTION 🌸

okay so these procedures are similar to string=?, string<?, etc., but they operate on the case-folded versions of the strings. case-folding is done as if by applying string-foldcase(3scm) to the strings. that's the whole magic trick ✨

🎀 RETURN VALUES 🎀

every call returns a single value, a boolean. yes bestie, just #t or #f — no extra luggage 🎀

🦋 EXAMPLES 🦋

here's the example energy, copied exactly:

(string-ci=? "z" "Z")  =>  #t

;; May return #t in R7RS.
(string-ci<? "z" "Z")  =>  #f

;; Can return #f in R7RS, and the characters may not be supported.
(string-ci=? "Straße" "Strasse")  =>  #t

(string-ci=? "Straße" "STRASSE")  =>  #t

(string-ci=? "XAOΣ" "χαoσ")  =>  #t

🌈 COMPATIBILITY 🌈

the basic idea of these procedures is the same in all RnRS revisions. however, there are some differences, and they're kinda important:

• R5RS and earlier reports only provided two-argument variants.
• R6RS implementations are mainly the same, except that they may behave differently depending on which version of the Unicode standard they support.
• R7RS implementations may lack support for some characters. The order is also implementation-defined, with lexicographical ordering only being one option.

💀 ERRORS 💀

this procedure can raise exceptions with the following condition types:

• &assertion (R6RS) — The wrong number of arguments was passed or an argument was outside its domain.
• R7RS — The assertions described above are errors. Implementations may signal an error, extend the procedure's domain of definition to include such arguments, or fail catastrophically.

👀 SEE ALSO 👀

string=?(3scm), string-foldcase(3scm) — go give 'em a look too, bestie 👀

⭐ STANDARDS ⭐

R4RS, IEEE Scheme, R5RS, R6RS, R7RS — the whole standards family reunion ⭐

🕰️ HISTORY 🕰️

these procedures first appeared in R2RS. a true icon from way back 🕰️

👑 AUTHORS 👑

this page is part of the scheme-manpages project. it includes materials from the RnRS documents. more information can be found at https://github.com/schemedoc/manpages/. shoutout to the project, fr fr 👑

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bye bestie!! this string-ci=?(3scm) page is dated 2022-04-08 — that's the cute sign-off from the scheme-manpages manual page, and you're all set to compare strings case-insensitively 💖✨