Can have an unicode ligature character fi (Unicode U+FB01) more than one representation in UTF8? Which one? For each normalization form?
Can have an unicode ligature character fi (Unicode U+FB01) more than one representation in
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Can have an unicode ligature character fi (Unicode U+FB01) more than one representation in UTF8? Which one? For each normalization form?
This depends on the meaning of “character,” which is rather obscure. In Unicode, “character” usually means a codepoint assigned to a character, and this does match exactly the intuitive concept of “character.”
A single codepoint, such as U+FB01, has only one representation in UTF-8, because UTF-8 defines an unambiguous algorithm for generating the encoded form.
An intuitive character, such as the fi ligature, may have different representations as a codepoint or as a sequence of codepoints, which each have UTF-8 representations. Unicode normalization rules define, in part, mappings between such alternatives.
But the compatibility mapping for U+FB01 (to U+0066 U+0069, i.e. “f” followed by “i”) does not preserve the identity of an intuitive character: the ligature is mapped to two normal letters.
On the other hand, you can ask for, or suggest, ligature behavior by inserting U+200D ZERO WIDTH JOINER (ZWJ) between two letters, like “f” and “i”. In a sense, the sequence U+0066 U+200D U+0069 is an alternative representation of the fi ligature, but this is not a formal property of character, and it depends on rendering software whether it pays attention to ZWJ.