this repo has no description
cmd/cue: expand the embed help section
Lifting text and examples from the proposal document,
but in shorter format for the sake of a quick summary
as well as dropping some details which don't matter to users.
Fixes #3268.
Signed-off-by: Daniel Martí <mvdan@mvdan.cc>
Change-Id: I8b90923dd43b5c706b9f8cf9dd0bd82513c1ad1d
Reviewed-on: https://review.gerrithub.io/c/cue-lang/cue/+/1199411
Reviewed-by: Matthew Sackman <matthew@cue.works>
Unity-Result: CUE porcuepine <cue.porcuepine@gmail.com>
TryBot-Result: CUEcueckoo <cueckoo@cuelang.org>
+28
-2
+28
-2
cmd/cue/cmd/help.go
+28
-2
cmd/cue/cmd/help.go
···
198
198
Use: "embed",
199
199
Short: "file embedding",
200
200
Long: `
201
-
The @embed directive can be used to load files of any type as part of CUE
202
-
evaluation.
201
+
The @embed attribute can be used to load files as part of CUE evaluation.
202
+
Embedding must be enabled by a file-level @extern(embed) attribute.
203
+
204
+
Embed a single file as follows, which must exist when evaluating:
205
+
206
+
@extern(embed)
207
+
208
+
package foo
209
+
210
+
a: _ @embed(file=foo.json)
211
+
212
+
Embed many files of the same type with a glob pattern,
213
+
which inserts one field per file matched:
214
+
215
+
b: _ @embed(glob=images/*.*, type=binary)
216
+
b: [string]: bytes
217
+
218
+
Note that "**" glob patterns are not supported at this time.
219
+
220
+
If the file extension in "file" or "glob" does not imply a file type,
221
+
it must be specified with the "type" encoding as shown above.
222
+
See the "filetypes" help topic for more.
223
+
224
+
Files containing multiple documents cannot be embedded directly.
225
+
For NDJSON or multi-document YAML files, embed as type=text
226
+
and use APIs like yaml.Extract to decode as a list.
227
+
228
+
Note that embedding cue files is not supported at this time.
203
229
204
230
Note: support for embed is experimental, and is enabled via
205
231
CUE_EXPERIMENT=embed.