mpdtexpand(1)

💖 mpdtexpand — the manual, but make it cute 💖

okay bestie, so this page right here? it's mpdtexpand(1), from the User Commands section, and it's genuinely one of those little utilities that does exactly one thing and does it flawlessly. no notes. let's get into it 💅

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✨ NAME ✨

mpdtexpand — expand a MPDT as an FST

like. that's the whole personality. it takes a MPDT and expands it into an FST. slay.

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🌸 SYNOPSIS 🌸

mpdtexpand [OPTIONS] in.mpdt [out.fst]

so you give it an input MPDT (in.mpdt), and if you want an output file (out.fst). the [OPTIONS] go up front because that's just how these things work, no cap.

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🦋 DESCRIPTION 🦋

Expands a (bounded-stack) MPDT as an FST.

periodt. that's the description. lowkey iconic that it needs no more than that.

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👑 OPTIONS 👑

okay so real talk first, bc this matters: boolean options accept either true or false as a value, or the implicit value true if neither value is specified. so like, --connect all by itself = --connect=true. the way that works is so convenient fr fr.

• --connect[=BOOLEAN] — trim the output. default: true.
• --fst_align[=BOOLEAN] — write FST data aligned where appropriate. default: false.
• --fst_compat_symbols[=BOOLEAN] — require symbol tables to match when appropriate. default: true.
• --fst_default_cache_gc[=BOOLEAN] — enable garbage collection of the cache. default: true.
• --fst_default_cache_gc_limit=N — set the cache byte size that triggers garbage collection. default: 1048576.
• --fst_error_fatal[=BOOLEAN] — if true, FST errors are fatal. otherwise, returned objects are flagged as bad — like, FSTs come back with the kError property set to true, and FST weights get set so that Member() returns false. default: true.
• --fst_field_separator=STRING — set the characters used as a separator between printed fields. default: " ".
• --fst_read_mode=STRING — set the default file reading mode for mappable files, either "read" or "map". default: "read".
• --fst_verify_properties[=BOOLEAN] — verify fst properties queried by TestProperties. default: false.
• --fst_weight_parentheses=STRING — set the characters enclosing the first weight of a printed composite weight (think pair weight, tuple weight, and derived classes) so nested composite weights do proper I/O. it must have size 0 (none) or 2 (open and close parenthesis). default: no parentheses.
• --fst_weight_separator=CHARACTER — set the character separator between printed composite weights. default: comma.
• --help[=BOOLEAN] — show usage information. default: false.
• --helpshort[=BOOLEAN] — show brief usage information. default: false.
• --keep_parentheses[=BOOLEAN] — keep MPDT parentheses in the result. default: false.
• --mpdt_parentheses=STRING — set the MPDT parenthesis label pairs. default: empty string.
• --save_relabel_ipairs=FILENAME — save input relabel pairs to a file. default: do not save.
• --save_relabel_opairs=FILENAME — save output relabel pairs to a file. default: do not save.
• --tmpdir=PATHNAME — set the temporary directory to use. default: /tmp.
• --v[=N] — set the verbosity level. default: 0.
• --weight=THRESHOLD — set the weight threshold. default: "".

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🔥 SEE ALSO 🔥

mpdtcompose(1), mpdtinfo(1), mpdtreverse(1)

(the whole mpdt friend group, honestly 🫶 go say hi)

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ok and a tiny lil heads-up bestie: --fst_weight_parentheses is not kidding about that size rule. size 0 or size 2, nothing in between. don't test it. 🙈

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that's the whole page!! 🎀 sending u off with the deets: this is OpenFst 1.8.5, dated Mar 2026, and you just read the mpdtexpand(1) manual. go expand something gorgeous, main character 💖✨🦋