Answer product-owner round 1: the release notes link the tagged README, say how to install and pin, name 64-bit targets, List and IsTemplate, the README says a nullable column needs a pointer, and item 89 names the changelog lines it changes

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@@ -7,62 +7,74 @@ replacement, and each removed path, column or flag.
## [Unreleased]
The first release: a Go library and a CLI that render locale-aware fake data from JSON
templates, and the data they ship with. The [README](README.md) documents each part.
templates, and the data they ship with. The
[README](https://github.com/larvit/fejkdata/blob/v0.1.0/README.md) documents each part.
Install the CLI with `go install github.com/larvit/fejkdata/cmd/fejkdata@v0.1.0`, or the
library with `go get github.com/larvit/fejkdata@v0.1.0`. Before 1.0.0 a minor may break,
and any release may change what a seed draws, so pin one exact version
([Versioning](https://github.com/larvit/fejkdata/blob/v0.1.0/README.md#versioning)).
### Added
- The CLI, `fejkdata`, renders exactly the template on its stdin and adds nothing:
`echo '{/sv_SE.person} hihi' | fejkdata` prints `Sara Eriksson hihi`. `--seed` makes a
run reproducible, `-n` repeats it, `--list` prints every path, and `--data-path` layers
a directory of your own data over the shipped set, or alone with `--no-shipped-data`.
`--format json|ndjson|csv|sql` writes a record's columns, one record per row. It exits
`0` on success, `1` on a runtime error such as data that fails to load, and `2` on
misuse.
- The library, `github.com/larvit/fejkdata`, for Go 1.22 or later. `New` loads the
modules `WithDataFS` names and the folders `WithDataPath` names, and fails, naming
`WithDataFS`, where neither is given; `WithSeed` makes its draws reproducible. `Fake`
renders a path, `FakeTemplate` and `NewTemplate` a template, `FakeRecord`,
`FakeRecordTemplate` and `NewRecordTemplate` a record, whose columns `JSON`,
`CSVHeader`, `CSVLine` and `SQLInsert` write as the CLI does, and `FakeStruct` fills a
struct's `fake:"…"` tagged fields. Data that fails to load gives an error matching
`ErrLoad`, and a record with no fields one matching `ErrNoColumns`.
- Package `github.com/larvit/fejkdata/cli` is the `fejkdata` command: `cli.Main(modules...)`
runs it over the modules given, so `cli.Main(append(data.Modules(), mydata)...)` builds a
CLI carrying your own data. That CLI names itself by the file it runs from, and its
`--version` prints its own module's version before fejkdata's.
- The template language ([Data format](README.md#data-format)). A node is a string, a
choice, a template, a table, a number or a boolean. A format string's `{…}` tokens read
sibling fields, references from the data root or the file's folder
(`{/sv_SE.person.last}`, `{.x}`, `{..x}`), builtins and names. Every `{…}` draws
afresh, and a name is the one way to keep a pick: `{/sv_SE.person as p}{p.first}
{p.last}` is one person. The builtins draw check digits (`luhn`, `mod11`, `ean`),
samples (`digits`, `int`, `float`, `uuid`, `ulid`, `iban`, `date`, `time` and more), a
counter (`seq`), arithmetic (`calc`) and transforms (`lowercase`, `uppercase`,
`ascii`). `New` refuses data that breaks the grammar, could mean two things or cannot
render a valid value.
- Records ([Records](README.md#records)): a template seen as columns. A column is a
string unless it declares a `datatype`, `integer`, `number` or `boolean`, and a `null`
item draws it as null.
- Tables ([Table](README.md#table)): a category naming a `rows` TSV beside it, with the
options `key`, `name`, `weight` and `parent`. A path selects a row by key or name,
`misc.territory[SE]`, descends to a linked table, `geo.SE.locality[Lund].street`, and
steps up to the parent row, `{/misc.timezone[Europe/Oslo]..territory.name}`.
- Data sources ([Data](README.md#data)): a directory is a namespace, and each JSON file
in it a category. A `.fejkdata.json` manifest at a source's root may carry a
`namespace`, the dot path the source mounts under, and an `index`, with which each
category loads on the first call reaching it.
- The CLI, `fejkdata`, renders exactly the template on its stdin and adds nothing: `echo
'{/sv_SE.person} hihi' | fejkdata` prints e.g. `Sara Eriksson hihi`. `--seed` makes a
run reproducible for one version and data, `-n` repeats it, `--list` prints every
path, and `--data-path` layers a directory of your own data over the shipped set, or
alone with `--no-shipped-data`. `--format json|ndjson|csv|sql` writes a record's
columns, one record per row. It exits `0` on success, `1` on a runtime error such as
data that fails to load, and `2` on misuse.
- The library, `github.com/larvit/fejkdata`, for Go 1.22 or later on a 64-bit target.
`New` loads the modules `WithDataFS` names and the folders `WithDataPath` names, and
fails, naming `WithDataFS`, where neither is given; `WithSeed` makes its draws
reproducible for one version and data. `Fake` renders a path, `FakeTemplate` and
`NewTemplate` a template, `FakeRecord`, `FakeRecordTemplate` and `NewRecordTemplate` a
record, whose columns `JSON`, `CSVHeader`, `CSVLine` and `SQLInsert` write as the CLI
does, and `FakeStruct` fills a struct's `fake:"…"` tagged fields. `List` gives every
path `Fake` renders, and `IsTemplate` tells an inline template from a path. Data that
fails to load gives an error matching `ErrLoad`, and a record with no fields one
matching `ErrNoColumns`.
- Package `github.com/larvit/fejkdata/cli` is the `fejkdata` command:
`cli.Main(modules...)` runs it over the modules given, so
`cli.Main(append(data.Modules(), mydata)...)` builds a CLI carrying your own data.
That CLI names itself by the file it runs from, and its `--version` prints its own
module's version before fejkdata's.
- The template language ([Data
format](https://github.com/larvit/fejkdata/blob/v0.1.0/README.md#data-format)). A node
is a string, a choice, a template, a table, a number or a boolean. A format string's
`{…}` tokens read sibling fields, references from the data root, the file's folder or
the folder above (`{/sv_SE.person.last}`, `{.x}`, `{..x}`), builtins and names. Every
`{…}` draws afresh, and a name is the one way to keep a pick: `{/sv_SE.person as
p}{p.first} {p.last}` is one person. The builtins draw check digits (`luhn`, `mod11`,
`ean`), samples (`digits`, `int`, `float`, `uuid`, `ulid`, `iban`, `date`, `time` and
more), a counter (`seq`), arithmetic (`calc`) and transforms (`lowercase`,
`uppercase`, `ascii`). `New` refuses data that breaks the grammar, could mean two
things or cannot render a valid value.
- Records ([Records](https://github.com/larvit/fejkdata/blob/v0.1.0/README.md#records)):
a template seen as columns. A column is a string unless it declares a `datatype`,
`integer`, `number` or `boolean`, and a `null` item draws it as null.
- Tables ([Table](https://github.com/larvit/fejkdata/blob/v0.1.0/README.md#table)): a
category naming a `rows` TSV beside it, with the options `key`, `name`, `weight` and
`parent`. A path selects a row by key or name, `misc.territory[SE]`, descends to a
linked table, `geo.SE.locality[Lund].street`, and steps up to the parent row,
`{/misc.timezone[Europe/Oslo]..territory.name}`.
- Data sources ([Data](https://github.com/larvit/fejkdata/blob/v0.1.0/README.md#data)):
a directory is a namespace, and each JSON file in it a category. A `.fejkdata.json`
manifest at a source's root may carry a `namespace`, the dot path the source mounts
under, and an `index`, with which each category loads on the first call reaching it.
- The shipped data, in Go packages that each export `FS` and `Modules()`:
`github.com/larvit/fejkdata/data/en_US` (package `enus`), `…/sv_SE` (`svse`),
`…/misc`, `…/geo/SE` (`geose`) and `…/geo/US` (`geous`). `data.Modules()`, from
`github.com/larvit/fejkdata/data`, lists every one, and the CLI carries them all.
[`DATA-LICENSES.md`](DATA-LICENSES.md) names each source.
[`DATA-LICENSES.md`](https://github.com/larvit/fejkdata/blob/v0.1.0/DATA-LICENSES.md)
names each source.
- `sv_SE` and `en_US`: an `address`, a `person` and more per locale. `sex`,
`first-name` and `last-name` are tables weighted by bearers, from SCB, the SSA and
the Census Bureau. A person's first name and sex agree, and so does an `en_US`
person's title; `person.prefix` is null where a person has no title. `sv_SE.personnummer` and
`sv_SE.samordningsnummer` draw Skatteverket's test series. `en_US.ssn` and
`en_US.itin` draw the ranges the SSA and the IRS assign, with the columns `area`,
`group` and `serial`, and `en_US.phone` draws an exchange NANPA may assign.
person's title; `person.prefix` is null where a person has no title.
`sv_SE.personnummer` and `sv_SE.samordningsnummer` draw Skatteverket's test series.
`en_US.ssn` and `en_US.itin` draw the ranges the SSA and the IRS assign, with the
columns `area`, `group` and `serial`, and `en_US.phone` draws an exchange NANPA may
assign.
- `misc`: IANA's registries of HTTP methods, protocols, ports and root-zone TLDs, the
HTTP status codes, ISO 3166-1 territories, ISO 4217 currencies with their CLDR
symbols, ISO 639 languages, the syslog severities, mime-db's media types, tzdb's
@@ -73,8 +85,8 @@ templates, and the data they ship with. The [README](README.md) documents each p
`locality`, `postal-code` and `street`, weighted by population and address counts
and built from SCB, GeoNames, Trafikverket NVDB, the US Census Bureau and Wikidata,
and an `address` record drawing a street and postal code inside one locality, which
`sv_SE.address` and `en_US.address` print. Every Swedish postort the import can place
ships with all its streets. Of the US incorporated places that hold most of some
postal code's land, every state capital but Honolulu, every place of 100,000 or more
and a population-weighted tenth of the rest ship, each with a quarter of its streets,
at least ten.
`sv_SE.address` and `en_US.address` print. Every Swedish postort the import can
place ships with all its streets. Of the US incorporated places that hold most of
some postal code's land, every state capital but Honolulu, every place of 100,000 or
more and a population-weighted tenth of them ship, each with a quarter of its
streets, at least ten.
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@@ -331,7 +331,7 @@ Swedish region but `abbr` on a US one.
## Library
```sh
go get github.com/larvit/fejkdata # Go 1.22+
go get github.com/larvit/fejkdata # Go 1.22+, 64-bit targets
```
```go
@@ -416,7 +416,7 @@ type Address struct {
a column of one record, its tag a path or an inline template — told apart by
`IsTemplate` — and its Go type the column's
[datatype](#datatype): a string, bool, integer or float kind, or a pointer to one,
which a [`null`](#null) item leaves nil. An integer stays within int64 whatever its
which a column that can be null requires and a [`null`](#null) item leaves nil. An integer stays within int64 whatever its
kind, and a value the kind cannot hold, such as `{int(0,300)}` in a `uint8`, is refused
naming a kind that holds it. The tags are a record's columns, so they share its
[names](#names): `First` tagged `{/sv_SE.person as p}{p.first}` and `Sex` tagged `{p.sex}`
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@@ -217,7 +217,7 @@
### 89. Fail `New` without `WithSeed`, naming the option, and seed the CLI from the system.
Goal 10.1 has the caller supply the seed, and today `New` without `WithSeed` seeds itself. It ships in 0.1.0, which already makes `New` refuse a call that names no data, so `New` breaks once, before anyone depends on it. Mark `WithSeed` required in the Library section's options table. `New`'s tests then stop swapping `randomBytes`. `fejkdata_test.go` swaps it today, and while that test runs, every `New` in the package fails.
Goal 10.1 has the caller supply the seed, and today `New` without `WithSeed` seeds itself. It ships in 0.1.0, which already makes `New` refuse a call that names no data, so `New` breaks once, before anyone depends on it. Mark `WithSeed` required in the Library section's options table. `New`'s tests then stop swapping `randomBytes`. `fejkdata_test.go` swaps it today, and while that test runs, every `New` in the package fails. Rewrite the changelog's library line to say `New` fails naming `WithSeed` where none is given, and its CLI line to say the CLI seeds from the system without `--seed`.
### 58. Ship prebuilt binaries, a container image, and packages for Homebrew, Scoop and the biggest Linux package managers, so the CLI needs no Go.