UNICODE_DERIVED_CORE(3)

💖 UNICODE_DERIVED_CORE — bestie edition 💖

okay so real talk, this is UNICODE_DERIVED_CORE(3) from the Courier Unicode Library, and it's literally a whole squad of nineteen little lookup girlies. They all do the same cute thing: you hand them a character, they tell you the tea about its derived core properties. no cap, that's the whole job. 🎀

This is unicode_derived_core_properties.

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✨ NAME ✨

unicode_derived_core_properties, unicode_derived_case_ignorable_lookup, unicode_derived_cased_lookup, unicode_derived_changes_when_casefolded_lookup, unicode_derived_changes_when_casemapped_lookup, unicode_derived_changes_when_lowercased_lookup, unicode_derived_changes_when_titlecased_lookup, unicode_derived_changes_when_uppercased_lookup, unicode_derived_default_ignorable_code_point_lookup, unicode_derived_grapheme_base_lookup, unicode_derived_grapheme_extend_lookup, unicode_derived_grapheme_link_lookup, unicode_derived_id_continue_lookup, unicode_derived_id_start_lookup, unicode_derived_incb_lookup, unicode_derived_lowercase_lookup, unicode_derived_math_lookup, unicode_derived_uppercase_lookup, unicode_derived_xid_continue_lookup, unicode_derived_xid_start_lookup — they look up derived core properties 💅

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🌸 SYNOPSIS 🌸

int unicode_derived_case_ignorable_lookup(char32_t c);

int unicode_derived_cased_lookup(char32_t c);

int unicode_derived_changes_when_casefolded_lookup(char32_t c);

int unicode_derived_changes_when_casemapped_lookup(char32_t c);

int unicode_derived_changes_when_lowercased_lookup(char32_t c);

int unicode_derived_changes_when_titlecased_lookup(char32_t c);

int unicode_derived_changes_when_uppercased_lookup(char32_t c);

int unicode_derived_default_ignorable_code_point_lookup(char32_t c);

int unicode_derived_grapheme_base_lookup(char32_t c);

int unicode_derived_grapheme_extend_lookup(char32_t c);

int unicode_derived_grapheme_link_lookup(char32_t c);

int unicode_derived_id_continue_lookup(char32_t c);

int unicode_derived_id_start_lookup(char32_t c);

int unicode_derived_incb_lookup(char32_t c);

int unicode_derived_lowercase_lookup(char32_t c);

int unicode_derived_math_lookup(char32_t c);

int unicode_derived_uppercase_lookup(char32_t c);

int unicode_derived_xid_continue_lookup(char32_t c);

int unicode_derived_xid_start_lookup(char32_t c);

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🦋 DESCRIPTION 🦋

So the way this works is: every one of these functions takes a character and looks up its various derived core properties. That's it. That's the gig. main character energy, honestly. 👑

One of them is the special one though, and you gotta know which 👀 — unicode_derived_incb_lookup() returns one of the UNICODE_DERIVED_INCB_value values from courier-unicode.h. Not a yes/no, an actual value, iykyk.

All the others — literally every single one of the other eighteen — return a non-0 value if the character has that derived property. So like, non-zero means "yep she's got it", and if it's not that, she doesn't. simple as. 💅

bestie reminder: unicode_derived_incb_lookup() does NOT follow the non-zero rule, it's out here handing you a whole UNICODE_DERIVED_INCB_value instead. don't get caught lacking. 🫶

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🌈 SEE ALSO 🌈

• TR-44[1]
• courier-unicode(7)

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💜 AUTHOR 💜

Sam Varshavchik

• Author

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🍓 NOTES 🍓

1. TR-44 https://www.unicode.org/reports/tr44/

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that's the whole page, periodt. ✨ this was Courier Unicode Library, version 04/12/2026, serving up UNICODE_DERIVED_CORE(3) — go forth and look up those properties, you absolute icon 👑💖