Reference · Strings

normalize

normalize(str, str | null=) -> str

What it does

The text in one Unicode form, so that text which looks the same is the same. é can be written as one character or as e followed by a combining accent; a keyboard on one system and a paste from another can give either, and ==, len and a database's unique index tell them apart. normalize(s) writes the composed form, NFC; the second argument picks another: "NFD" (decomposed), "NFKC" or "NFKD", which also fold look-alikes such as fi into fi. It runs the same on the server and in the browser.

Examples

let typed = "café"let pasted = "cafe\u{301}"print(typed == pasted, normalize(typed) == normalize(pasted))print(len(pasted), len(normalize(pasted)), len(normalize(typed, "NFD")))

false true5 4 5

Edge cases

• Compare user names and emails after normalize(lower(trim(s)), "NFKC"), and keep them so in the database, so two accounts cannot share one visible name.
• The form's name may be in either case. Text already in the form comes back the same, and an empty text is empty.

print(normalize("file", "nfkc"), normalize("file"), normalize("Ⅻ", "NFKD"), normalize(""))

file file XII 

Errors

A form that is none of the four is a runtime error.

normalize("x", "NFX")

line 1: `normalize`: the form is "NFC", "NFD", "NFKC" or "NFKD", got "NFX"

Chaining

print("  Cafe\u{301}  " | trim() | normalize() | lower())

café

See also

lower, trim, len

Edit this page on GitHub · every example's output was made by running it (tools/refcheck.mjs) · questions on Discord or r/quillo