BSON_APPEND_REGEX(3)

💅 BSON_APPEND_REGEX 💅

okay bestie, this one's from the libbson girlies — it's the BSON_APPEND_REGEX(3) page and honestly it's giving "small function, big slay" ✨

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✨ SYNOPSIS ✨

so there's a macro and a function, because of course there is 💅

#define BSON_APPEND_REGEX(b, key, val, opt) \
   bson_append_regex (b, key, (int) strlen (key), val, opt)

bool
bson_append_regex (bson_t *bson,
                   const char *key,
                   int key_length,
                   const char *regex,
                   const char *options);

like, the macro is just the function but it does the strlen() for you so you don't have to. main character energy honestly 🎀

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🌸 PARAMETERS 🌸

• bson — a bson_t. that's the whole vibe. the document you're adding to 💖
• key — an ASCII C string with the name of the field. yep. just the name. ngl ASCII only, keep it cute 🦋
• key_length — the length of key in bytes, or -1 if you want it to figure that out with strlen(). lowkey the lazy-girl option and we respect it 🙈
• regex — an ASCII string containing the regex. the actual pattern, bestie 🔥
• options — an optional string containing the regex options as a string. optional!! so you can absolutely skip it 💜

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🦋 DESCRIPTION 🦋

so what it does: it appends a brand new field onto bson, and the type is BSON_TYPE_REGEX — iconic, we love a dedicated regex type 💅

regex should be the regex string. options should contain the options for the regex. simple, clean, no cap ✨

and the valid characters for options? bestie I got you, here's the whole list 🎀

• 'i' — for case-insensitive. so ABC and abc are the same thing, slay 💖
• 'm' — for multiple matching 👑
• 'x' — for verbose mode 🌸
• 'l' — to make w and W locale dependent. yep, the lowercase and uppercase ones, exactly those 🌈
• 's' — for dotall mode, which means '.' matches everything. every single thing. periodt ⭐
• 'u' — to make w and W match unicode 🦋

fr fr, those are the exact characters — don't go inventing new ones, bestie 😭

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⭐ RETURNS ⭐

Returns true if the operation was applied successfully. if it worked, it worked 💖

but heads up: the function will fail if appending the regex grows bson larger than INT32_MAX. like, that's the ceiling. if you blow past it, it's not happening, sorry not sorry 💀

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👑 AUTHOR 👑

MongoDB, Inc — the literal authors, we stan 🫶

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🧚 COPYRIGHT 🧚

2009-present, MongoDB, Inc. — all rights reserved, all vibes preserved 🌸

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and that's the whole page, bestie!! this was libbson 2.5.6, dated Oct 09, 2026 — go forth and append those regexes, you absolute icon 💅✨🍓