fstpush(1)

💖 fstpush — like, the FST weight & label pusher, bestie 💖

okay so sit DOWN because we're talking about fstpush, which lives in section 1 of the manual (user commands, the fun section) and is literally here to push weights and/or olabels around inside an FST. that's the whole vibe. 🦋

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✨ NAME ✨

fstpush — push weights or labels in an FST 👑

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✨ SYNOPSIS ✨

fstpush [OPTIONS] [in.fst [out.fst]]

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🌸 DESCRIPTION 🌸

Pushes weights and/or olabels in an FST. that's it, that's the girl. she's simple, she's effective, she's iconic. 💅

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🎀 OPTIONS 🎀

okay bestie real talk, first the rules of the house: boolean options take either true or false as a value, or if you say nothing at all they just implicitly mean true. no cap. 🫶

• --delta=VALUE — sets the comparison/quantization delta. default: 0.000976562. tiny number, big responsibilities ✨
• --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. she cleans up after herself, we love that 🌈
• --fst_default_cache_gc_limit=N — sets the cache byte size that triggers garbage collection. default: 1048576.
• --fst_error_fatal[=BOOLEAN] — if true, FST errors are fatal. otherwise, the returned objects get flagged as bad instead: for example, FSTs come back with the kError property set to true, and FST weights get set so that Member() returns false. default: true. 💀 yeah this one does not play.
• --fst_field_separator=STRING — sets the characters used as a separator between printed fields. default: " ". yes that's real, those are spaces, don't @ me 😭
• --fst_read_mode=STRING — sets 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 — sets 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. must have size 0 (none) or 2 (open and close parenthesis). default: no parentheses.
• --fst_weight_separator=CHARACTER — sets the character separator between printed composite weights. default: comma.
• --help[=BOOLEAN] — show usage information. default: false.
• --helpshort[=BOOLEAN] — show brief usage information. default: false.
• --push_labels[=BOOLEAN] — push output labels. default: false.
• --push_weights[=BOOLEAN] — push weights. default: false.
• --remove_common_affix[=BOOLEAN] — remove common prefix/suffix when pushing labels. default: false.
• --remove_total_weight[=BOOLEAN] — remove total weight when pushing weights. default: false.
• --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 — sets the temporary directory to use. default: /tmp.
• --to_final[=BOOLEAN] — push to final states. default: false, which means push to initial states. pick your direction, babe 🧚
• --v[=N] — sets the verbosity level. default: 0.

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👑 SEE ALSO 👑

she runs with a whole crew, fr fr, and every single one of them is getting a shoutout:

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), fstproject(1), fstprune(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). the whole friend group showed up, ate, left no crumbs 🫶💖

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so yeah, that's fstpush — straight out of OpenFst 1.8.5, dated Mar 2026. go push some weights bestie, you got this 💅✨🌟