fstproject(1)

✨ fstproject — the manual page, but make it cute ✨

okay so bestie, welcome to fstproject(1), straight outta the User Commands manual 💖

🌸 NAME 🌸

fstproject — project a transduction onto its input or output language 🦋

🎀 SYNOPSIS 🎀

fstproject [OPTIONS] [in.fst [out.fst]]

💅 DESCRIPTION 💅

It projects a transduction onto its input or output language. that's it, that's the whole vibe. literally iconic behavior.

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👑 OPTIONS 👑

quick thing before we dive in, no cap: boolean options accept either true or false as a value, or the implicit value true if neither value is specified. so like, you can just say the flag and it's already on. slay.

• --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 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. for example, FSTs are returned with the kError property set to true, and FST weights set so that Member() returns false. default: true. (this one is highkey serious bestie, don't play with it 🙈)
• --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 (e.g., pair weight, tuple weight, and derived classes) to ensure proper I/O of nested composite weights. 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.
• --project_output[=BOOLEAN] — project on the output language. default: false (project on the input language). the main character option fr fr 💫
• --save_relabel_ipairs=FILENAME — save input relabel pairs to file. default: do not save.
• --save_relabel_opairs=FILENAME — save output relabel pairs to file. default: do not save.
• --tmpdir=PATHNAME — set the temporary directory to use. default: /tmp.
• --v[=N] — set the verbosity level. default: 0.

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🫶 SEE ALSO 🫶

the whole friend group showed up, we love a squad 💜

fstarcsort(1), fstclosure(1), fstcompile(1), fstcompose(1), fstcompress(1), fstconcat(1), fstconnect(1), fstconvert(1), fstdeterminize(1), fstdifference(1), fstdisambiguate(1), fstdraw(1), fstencode(1), fstepsnormalize(1), fstequal(1), fstequivalent(1), fstinfo(1), fstintersect(1), fstinvert(1), fstisomorphic(1), fstlinear(1), fstloglinearapply(1), fstmap(1), fstminimize(1), fstprint(1), fstprune(1), fstpush(1), fstrandgen(1), fstrelabel(1), fstreplace(1), fstreverse(1), fstreweight(1), fstrmepsilon(1), fstshortestdistance(1), fstshortestpath(1), fstsymbols(1), fstsynchronize(1), fsttopsort(1), fstunion(1)

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🌈 okay that's the whole page bestie, you ate it. this was OpenFst 1.8.5, dated Mar 2026 — go project something gorgeous 💅✨