The uniq verb outputs only the group-by columns, and issue #1075 asks
for a way to deduplicate on some fields while keeping the rest. Miller
already supports this via "head -n 1 -g", but that wasn't discoverable
from uniq's help text or its reference-verbs section. Add a note to
"mlr uniq --help" and a short recipe (with live examples) to the uniq
section of the verbs reference, and regenerate the derived man page,
docs, and CLI-help golden files.
Co-authored-by: Claude Fable 5 <noreply@anthropic.com>
When the skip-trivial-records verb is in the then-chain, the CSV/TSV
record-readers now silently skip trivial (all-fields-empty) input lines
-- notably blank lines at the end of a CSV file -- instead of raising a
fatal header/data length mismatch. The user has explicitly asked for
trivial records to be skipped, so mlr now exits 0 in this case.
The verb's CLI parser sets a new ReaderOptions.SkipTrivialRecords flag,
which the CSV and TSV readers consult only on the would-be-fatal
mismatch path, so:
* Behavior without the verb is unchanged: blank lines still error.
* Genuinely ragged non-trivial records still error even with the verb.
* --allow-ragged-csv-input behavior is unchanged.
Fixes#1535.
Co-authored-by: Claude Fable 5 <noreply@anthropic.com>
With multiple regexes, 'mlr reorder -r' previously emitted all matched
fields in record order, ignoring the order the regexes were given. Now
matched fields are grouped by regex-list order (first regex's matches
first, then the second's, etc.); within each group, fields keep their
record order. A field matching multiple regexes is claimed by the first
one. This makes 'reorder -r' consistent with 'cut -orf' and satisfies
the original request in #1325: -r '^YYY,^XXX' puts YYY-prefixed fields
first, then XXX-prefixed fields, then the rest. Applies to -e, -b, and
-a modes as well.
Co-authored-by: Claude Fable 5 <noreply@anthropic.com>
The summary verb's field_type column shows values like "string-int" or
"empty-string" for columns containing values of mixed inferred types:
all types encountered across records are printed, hyphen-joined, in the
order first encountered. Add a note to the verb's help text explaining
this, and regenerate the man page, docs, and golden test output.
Co-authored-by: Claude Fable 5 <noreply@anthropic.com>
The tee verb passed the same record pointer both to its file-output
handler (which writes asynchronously on another goroutine, and whose
buffering formats like pprint/json can hold records until close) and
downstream in the verb chain, where subsequent verbs mutate records in
place. Downstream mutations could therefore leak into the tee'd output:
mlr tee -p cat then cat -n then nothing <<EOF
a=1,b=2
a=3,b=4
a=5,b=6
EOF
emitted "n=3,a=5,b=6" for the last tee'd record, and with pprint/json
tee formats every record picked up downstream fields.
Fix: give the file-writer its own deep copy of the record. Same fix
applied to the split verb when -v (emit downstream) is used, which
shared records with downstream the same way.
Co-authored-by: Claude Fable 5 <noreply@anthropic.com>
The join verb's help text listed only '-i {one of csv,dkvp,nidx,pprint,xtab}'
for overriding the left-file input format, but the verb also accepts the
--icsv/--ijson-style main-flag shorthands (and formats beyond the five
listed, e.g. json and tsv), since unrecognized verb flags fall through to
the main flag table. Update the usage text to say so, and regenerate the
man page and docs content that embed this help output.
Fixes#444.
Co-authored-by: Claude Fable 5 <noreply@anthropic.com>
The uniq verb writes its group-by fields in the order they are named
with -g or -f, not in the order they appear in the input records
(unlike cut, which preserves input order unless -o is given). Per
discussion on #962, document this in the verb help text rather than
change long-standing output ordering. Regenerate the man page and the
docs pages which embed the verb help.
Co-authored-by: Claude Fable 5 <noreply@anthropic.com>
One output record per input field: types seen with counts, occurrence
count, null count, cardinality, min/max, and -- for fields within the
-n/--max-values cap -- the complete distinct-value list in first-seen
order. `mlr --ojson describe` is the machine-readable form; nested
types/values flatten in tabular formats.
Co-authored-by: Claude Fable 5 <noreply@anthropic.com>
Lets an agent type-check a DSL expression before spending a full input
pass. `mlr put --explain '...'` (and filter) runs the existing
parse -> ValidateAST -> CST build -> Resolve path, then:
- valid: prints "mlr {put,filter}: DSL expression is valid." and exits 0
- invalid: returns the build error up the normal path, so --errors-json
emits a structured document; exits 1
- -W with fatal warnings: reports and exits 1
The gate lives in the pass-two constructor, before any input file is
opened, so no input stream is read (verified with a nonexistent input
file still validating OK).
Also categorize bare "parse error: ..." messages from the DSL parser as
kind "dsl-parse-error" rather than "generic" (climain/errors_json.go),
so --explain --errors-json gives an agent a useful error kind. The CSV
reader's "parse error on line ..." is stream-time and never reaches this
command-line-parse categorizer.
Tests: dsl-explain/0001-0004 regression cases (valid put/filter, invalid
plain, invalid --errors-json) and categorize unit tests. Regenerated
verb docs, manpage, and the help usage-verbs golden case.
The older -X ("exit after parsing") still exits 0 even on a parse error;
left as-is since --explain is the correct validation path.
Co-authored-by: Claude Fable 5 <noreply@anthropic.com>
* Tier-2 structured verb options: OptionSpec, initial migration (#2098)
PR 3 of the AI-friendly roadmap (plans/plan-2098-llm.md).
Infrastructure:
- Add OptionSpec{Flag,Arg,Type,Desc,Repeatable,Values} to
pkg/transformers/aaa_record_transformer.go alongside TransformerSetup.
Type is one of: bool, string, int, float, csv-list, regex, filename,
format, enum. For type=="enum", Values lists the valid choices.
- Add Options []OptionSpec to TransformerSetup (nil = not yet migrated).
- Emit Options in VerbInfoForJSON (omitempty so unmigrated verbs stay
backward-compatible; agents check key presence for Tier-2 availability).
UsageText is always present as the Tier-1 prose fallback.
- Add VerbOptionsNilCheck() in aaa_verb_options_check.go: progress report
of migrated vs. unmigrated verbs, analogous to FLAG_TABLE.NilCheck().
- Wire verb-options-nil-check into mlr help (internal/docgen section).
Initial migration (5/70 verbs):
- nothing: empty Options (no verb-specific options, explicitly migrated)
- cat: -n (bool), -N (string), -g (csv-list), --filename, --filenum (bool)
- head: -g (csv-list), -n (int)
- tail: -g (csv-list), -n (int)
- tee: -a, -p (bool)
Tests:
- 5 new unit tests in aaa_transformer_json_test.go covering migrated/
unmigrated paths, field population, JSON round-trip, and key-presence.
- Regression test case 0003: mlr help verb-options-nil-check golden output.
Co-Authored-By: Claude Sonnet 4.6 (1M context) <noreply@anthropic.com>
* Migrate all 70 verbs to structured OptionSpec; bump catalog schema to v2
Completes the Tier-2 migration started in the previous commit. Every verb
in TRANSFORMER_LOOKUP_TABLE now has a non-nil Options field.
- Workflow-migrated all 65 remaining verbs. Each Setup var now carries
Options: []OptionSpec{...} with Flag/Arg/Type/Desc fields. Verbs with
no verb-specific options (altkv, check, group-like, nothing, etc.) use
an empty slice to signal "migrated but no options."
- Drop `omitempty` from VerbInfoForJSON.Options: empty slices were silently
dropped, making migrated-no-option verbs indistinguishable from unmigrated
ones in JSON. Without omitempty: null=unmigrated, []=migrated-no-options,
[...]= migrated-with-options. Bump catalogSchemaVersion 1→2 for this shape
change.
- Replace the two "unmigrated-verb" unit tests (which used stats1 as an
example) with TestAllVerbsFullyMigrated (asserts every verb has non-nil
Options) and TestAllVerbsHaveOptionsKeyInJSON (asserts every migrated
verb emits the "options" key in JSON).
- Regenerate test/cases/cli-help/0003/expout: now reads
"Verb options migration: 70/70 migrated."
Co-Authored-By: Claude Sonnet 4.6 (1M context) <noreply@anthropic.com>
* remove a transitional helper
* git rms
* Render verb usage Options blocks from structured OptionSpec
Each verb's usage message and its Tier-2 OptionSpec list previously
duplicated the option text. New WriteVerbOptions (aaa_verb_usage.go)
renders the "Options:" block from the specs: aligned flag column,
descriptions word-wrapped at 80, uniform trailing -h|--help line.
- OptionSpec gains Aliases (JSON "aliases") so long-form spellings
like join's --lk|--left-keep-field-names survive in both outputs
- All 70 verbs migrated; options literals hoisted to package-level
vars (usage funcs can't reference their Setup var without a Go
init cycle)
- Hand-written per-option details the specs had condensed away are
merged into Desc, enriching the JSON catalog
- Non-option prose (examples, cross-references, dynamic accumulator
listings) kept verbatim
- Regenerated the six usage-embedding regression expectations and
the two affected doc pages
Co-Authored-By: Claude Fable 5 <noreply@anthropic.com>
* Fix pre-existing usage-text bugs surfaced by the OptionSpec migration
- gap: usage said "One of -f or -g is required" but the parser takes
-n or -g
- seqgen: drop description line copy-pasted from cat ("Passes input
records directly to output...") which contradicted "Discards the
input record stream"
- utf8-to-latin1: description read inverted ("from Latin-1 to UTF-8")
- sec2gmtdate: usage said "../c/mlr" instead of "mlr"
- top: document the accepted-but-undocumented --max flag
- stats2: add linreg-pca to the -a enum values, matching the runtime
accumulator table
Regression expectations and docs regenerated accordingly.
Co-Authored-By: Claude Fable 5 <noreply@anthropic.com>
* Fix check usage sentence order; stats1 usage blank line to usage stream
- check: the description's second and third lines were swapped,
reading "Consumes records without printing any output, / Useful for
doing a well-formatted check on input data. / with the exception
that warnings are printed to stderr."
- stats1: a bare fmt.Println() in the usage func wrote its blank line
to process stdout instead of the usage output stream
Regression expectation and docs regenerated.
Co-Authored-By: Claude Fable 5 <noreply@anthropic.com>
---------
Co-authored-by: Claude Sonnet 4.6 (1M context) <noreply@anthropic.com>
* refine the plan
* Fix all staticcheck lint findings (uncapped)
golangci-lint's default max-same-issues=3 was hiding most of the backlog:
the true pre-fix count was 69 staticcheck findings, not 34. This fixes all
of them, driving staticcheck to zero:
- ST1023/QF1011 (37): omit explicit types inferred from the RHS
- S1009/S1031 (15): drop redundant nil checks before len()/range
- SA9003 (9): remove comment-only empty branches, keeping the comments
- QF1007 (3): merge conditional assignment into declaration
- QF1006 (3): lift break conditions into loop conditions
- QF1001 (3): apply De Morgan's law / name the negated predicate
Also updates plans/lintfixes.md with the cap discovery and the corrected
errcheck picture (1202 uncapped, ~949 of them fmt.Fprint*).
Co-Authored-By: Claude Fable 5 <noreply@anthropic.com>
* Drive errcheck to zero: config for bulk categories, propagate real errors
Adds .golangci.yml with errcheck exclude-functions for fmt.Fprint* (usage
printers), (*bufio.Writer).Write/WriteString (sticky errors, surfaced at the
now-checked final Flush), and (*strings.Builder).WriteString; pins
max-issues-per-linter/max-same-issues to 0 so CI reports true counts.
Real error paths now propagate instead of being dropped:
- Finalize{Reader,Writer}Options in join/put/filter/split/tee and the
repl/script entry points: 'mlr join -i badformat' now errors instead of
silently using wrong separators
- final output-stream Flush in pkg/stream: write failure no longer exits 0
- DSL emit/print/dump redirect writes, matching their sibling branches
- CSV writer WriteCSVRecordMaybeColorized, close-time Flush in file output
handlers, ENV[...] Setenv, REPL record-write and redirect-close errors
- termcvt write-side Close before rename (had "TODO: check return status")
The rest are deliberate ignores, marked with _ = and a comment where the
reason isn't obvious: unset-of-missing-path no-ops, read-side closes,
mid-stream FlushOnEveryRecord, init-time strftime registrations, in-memory
usage-capture pipes, and regtest-harness env/temp-file teardown.
golangci-lint now reports 0 issues on ./cmd/mlr ./pkg/... with all caps off.
Co-Authored-By: Claude Fable 5 <noreply@anthropic.com>
---------
Co-authored-by: Claude Fable 5 <noreply@anthropic.com>
Replaces 100+ if/else-if chains on a single variable with tagged switch
statements across 72 files. The bulk are transformer option-parsing loops
(switch on opt string), plus a handful of value-dispatch sites in mlrval,
dsl/cst, repl, lib, auxents, and bifs. One case (surv.go) required a
labeled break to preserve the loop-exit behavior of the original else branch.
Fixes staticcheck QF1003 findings.
Co-authored-by: Claude Sonnet 4.6 (1M context) <noreply@anthropic.com>
Emit Miller's existing help catalog (verbs, functions, flags, keywords)
as structured JSON so AI agents and tooling can model Miller's surface
without scraping prose. The --json token may appear anywhere on a
`mlr help ...` command line; plain text help is unchanged.
mlr help --json # full catalog
mlr help verb cat --json # one or more verbs
mlr help function splitax --json # one or more functions
mlr help flag --ifs --json # one or more flags
mlr help keyword ENV --json # one or more keywords
Functions and flags serialize fully (name/class/arity/help/examples;
section/name/alt_names/arg/help). Verbs carry a summary, ignores_input,
and captured raw usage_text as a Tier-1 fallback, since per-verb options
are prose-only today (each verb hand-writes its UsageFunc). Structured
verb options are a planned follow-on (see #2098).
This is a serialization layer over the existing registries -- no
refactor of the text-help path.
Co-authored-by: Claude Opus 4.8 <noreply@anthropic.com>
* initial attempt
* fix bash
* fix zsh
* Add shell-completion docs page
Documents the new 'mlr completion {bash,zsh}' feature: the then-chain
context model, install instructions for bash and zsh (including the macOS
bash-3.2 'eval' caveat and zsh compinit self-init), and examples of
context-aware completion. Added to the nav under "Miller in more detail".
Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com>
* Add enum value completion for format and separator flags
Completes the argument value for arg-taking main flags whose values are a
known set: file-format names for -i/-o/--io, separator aliases for
--ifs/--ofs/--ips/etc., and regex-separator aliases for --ifs-regex/--ips-regex.
Other arg-taking flags continue to fall back to filename completion.
Candidate sets come from new cli getters (GetFileFormatNames,
GetSeparatorAliasNames, GetSeparatorRegexAliasNames) that read the same maps
Miller uses at runtime, so there is no separate list to keep in sync. The
command-line walk now records which flag a value position belongs to.
Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com>
* Include format-conversion keystroke-savers in bare-dash completion
Reverts the suppression of --c2j/--x2y-style flags from 'mlr -<TAB>'. The full
set of main flags (297) is now offered, matching what is valid on the command
line. GetFlagNames no longer takes an includeSuppressed argument.
Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com>
* Complete terminal subcommands and top-level help/version flags
'mlr <TAB>' now offers subcommand names (help, version, repl, regtest, script,
completion, terminal-list) alongside verb names, and 'mlr -<TAB>' offers the
top-level terminal flags (-h, --help, --version, --bare-version, and the help
shorthands -g/-l/-L/-f/-F/-k/-K). Subcommand names are offered only as the
first non-flag token, where they are valid.
To let the completion engine know these names without an import cycle
(pkg/terminals imports pkg/terminals/completion), the canonical terminal names
and version-flag spellings are factored into a new leaf package
pkg/terminals/registry, imported by pkg/terminals, pkg/climain, and completion.
The help-flag spellings come from a new help.GetTerminalFlagNames derived from
the existing shorthand table, so nothing drifts.
Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com>
* Complete 'mlr help' topics and topic arguments
'mlr help <TAB>' now completes help topics (flags, verb, function, keyword,
list-verbs, ...), and topics that take a name argument complete it too:
'mlr help verb <TAB>' -> verb names, 'mlr help function <TAB>' -> function
names, 'mlr help keyword <TAB>' -> keyword names, 'mlr help flag <TAB>' ->
flag names. 'mlr completion <TAB>' completes bash/zsh.
A terminal subcommand consumes the rest of the command line, so the walk now
returns a ctxTerminalArgs context carrying the terminal name and the words
typed after it. New getters supply the candidate names without drift:
help.GetTopicNames, help.GetFunctionNames/GetKeywordNames (wrapping new
cst.BuiltinFunctionManager.GetBuiltinFunctionNames and cst.GetKeywordNames).
Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com>
* docs-neaten
* Move flag-value-candidate logic into pkg/cli; fix verb-flag collision
The mapping of which flags take a format/separator/regex-separator argument is
flag metadata, so it now lives with the flags in pkg/cli as
cli.FlagValueCandidates, alongside the existing GetFileFormatNames /
GetSeparatorAliasNames getters, replacing the maps that were in
pkg/terminals/completion/value_completion.go (now removed).
This also fixes a bug: value completion now applies only to main flags, not to
identically-spelled verb flags. Previously 'mlr uniq -o <TAB>' offered file
formats because uniq's -o (an output field name) collided with the main -o
format flag; it now correctly falls back to filename completion.
Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com>
---------
Co-authored-by: Claude Opus 4.8 <noreply@anthropic.com>
Inspired by GNU head & tail, they match their behavior while supporting
the usual grouping operations.
Co-authored-by: John Kerl <kerl.john.r@gmail.com>
seqgen.Transform was generating its full sequence on every call,
including once per upstream record. When chaining two seqgens of
N records each, the second produced N+1 copies of N records in
memory (O(N²)) before writing only the first N. Fix: return
immediately for non-EOS input; generate the sequence only when
the upstream end-of-stream arrives, which is the correct
semantics for a verb that discards its input record stream.
Co-authored-by: Claude Sonnet 4.6 (1M context) <noreply@anthropic.com>
The --lp/--rp prefixes and -j output-field rename were applied only to
paired records, leaving unpaired records emitted via --ul/--ur with their
original (left/right) field names. This broke downstream operations like
unsparsify that expected consistent column names across paired and
unpaired output.
Co-authored-by: Claude Opus 4.7 (1M context) <noreply@anthropic.com>
When using --fr (regex field selector) with stats1 -a null_count, void
(empty) field values were unconditionally skipped in
ingestWithValueFieldRegexes, causing null_count to always report 0.
The non-regex path (ingestWithoutValueFieldRegexes) already had a special
case that allows void values through for null_count accumulators. This
commit adds the same exception to the regex path.
Fixes#1639
Co-authored-by: cobyfrombrooklyn-bot <cobyfrombrooklyn-bot@users.noreply.github.com>
* Switch to integer ranges in for loops
Signed-off-by: Stephen Kitt <steve@sk2.org>
* Switch to slices functions where appropriate
A number of utility functions can be replaced outright; since Miller
can technically be used as a library, these are deprecated rather than
removed. go:fix directives ensure that they can be replaced
automatically.
Signed-off-by: Stephen Kitt <steve@sk2.org>
* Switch to reflect.TypeFor
This is slightly more efficient than TypeOf when the type is known at
compile time.
Signed-off-by: Stephen Kitt <steve@sk2.org>
* Switch to strings.SplitSeq instead of strings.Split
SplitSeq results in fewer allocations.
Signed-off-by: Stephen Kitt <steve@sk2.org>
* Drop obsolete build directives
Signed-off-by: Stephen Kitt <steve@sk2.org>
* Use min/max instead of explicit comparisons
Signed-off-by: Stephen Kitt <steve@sk2.org>
* Append slices instead of looping
Signed-off-by: Stephen Kitt <steve@sk2.org>
---------
Signed-off-by: Stephen Kitt <steve@sk2.org>
Add a surv verb to estimate a survival curve using Kaplan-Meier. It
requires duration and status (event or censored) columns, and outputs
each distinct duration and corresponding probability of survival.