Tool for doc lookups, usages, and quizzes of Janet's PEG specials.
pdoc manifests itself as a command line tool as well as a macro.
Quick:
jpm install https://github.com/sogaiu/janet-pegdoc
Manual:
git clone https://github.com/sogaiu/janet-pegdoc
cd janet-pegdoc
jpm install
In either case, success should lead to the command pdoc being
available on PATH and a pegdoc directory within a directory on
JANET_PATH.
Show doc and usages for a peg special.
$ pdoc any
`(any patt)`
Matches 0 or more repetitions of `patt`
####################################################################
# any with empty string
(peg/match ~(any "a")
"")
# =>
@[]
# any
(peg/match ~(any "a")
"aa")
# =>
@[]
# any with capture
(peg/match ~(capture (any "a"))
"aa")
# =>
@["aa"]
Show just doc for the peg special to.
$ pdoc -d to
`(to patt)`
Match up to `patt` (but not including it).
If the end of the input is reached and `patt` is not matched, the entire
pattern does not match.
Show just usages for a peg special.
$ pdoc -u if
(peg/match ~(if 1 "a")
"a")
# =>
@[]
(peg/match ~(if 5 (set "eilms"))
"smile")
# =>
@[]
(peg/match ~(if 5 (set "eilms"))
"wink")
# =>
nil
Ask for a quiz question and have your answer checked.
$ pdoc --quiz replace
(peg/match ~(replace (sequence (capture "ca")
(_______ "t"))
,(fn [one two]
(string one two "alog")))
"cat")
# =>
@["catalog"]
What value could work in the blank?
Show all peg specials.
$ pdoc
Primitive Patterns
Integer (..., -1, 0, 1, ...)
range = (range r1 ?r2 ... ?rn)
set = (set chars)
String ("...")
Boolean (true, false)
Combining Patterns
any = (any patt)
at-least = (at-least n patt)
at-most = (at-most n patt)
backmatch = (backmatch ?tag)
between (opt, ?) = (between min max patt)
choice (+) = (choice patt-1 patt-2 ...)
if = (if cond patt)
if-not = (if-not cond patt)
look (>) = (look offset ?patt)
not (!) = (not patt)
repeat (0, 1, 2, ...) = (repeat n patt)
sequence (*) = (sequence patt-1 patt-2 ...)
some = (some patt)
split = (split sep patt)
sub = (sub window-patt patt)
thru = (thru patt)
to = (to patt)
Captures
accumulate (%) = (accumulate pat ?tag)
argument = (argument n ?tag)
backref (->) = (backref prev-tag ?tag)
capture (<-, quote) = (capture patt ?tag)
cmt = (cmt patt fun ?tag)
column = (column ?tag)
constant = (constant k ?tag)
drop = (drop patt)
error = (error ?patt)
group = (group patt ?tag)
int = (int n ?tag)
int-be = (int-be n ?tag)
lenprefix = (lenprefix n patt)
line = (line ?tag)
nth = (nth index patt ?tag)
number = (number patt ?base ?tag)
only-tags = (only-tags patt)
position ($) = (position ?tag)
replace (/) = (replace patt subst ?tag)
uint = (uint n ?tag)
uint-be = (uint-be n ?tag)
unref = (unref rule ?tag)
Built-ins
:a = (range "AZ" "az")
:d = (range "09")
:h = (range "09" "AF" "af")
:s = (set " \0\f\n\r\t\v")
:w = (range "09" "AZ" "az")
:A = (if-not :a 1)
:D = (if-not :d 1)
:H = (if-not :h 1)
:S = (if-not :s 1)
:W = (if-not :w 1)
:a+ = (some :a)
:d+ = (some :d)
:h+ = (some :h)
:s+ = (some :s)
:w+ = (some :w)
:A+ = (some :A)
:D+ = (some :D)
:H+ = (some :H)
:S+ = (some :S)
:W+ = (some :W)
:a* = (any :a)
:d* = (any :d)
:h* = (any :h)
:s* = (any :s)
:w* = (any :w)
:A* = (any :A)
:D* = (any :D)
:H* = (any :H)
:S* = (any :S)
:W* = (any :W)
Aliases
(! patt) = (not patt)
($ ?tag) = (position ?tag)
(% patt ?tag) = (accumulate patt ?tag)
(* patt-1 ... patt-n) = (sequence patt-1 ... patt-n)
(+ patt-1 ... patt-n) = (choice patt-1 ... patt-n)
(-> prev-tag ?tag) = (backref prev-tag ?tag)
(/ patt subst ?tag) = (replace patt subst ?tag)
(<- patt ?tag) = (capture patt ?tag)
(> offset ?patt) = (look offset ?patt)
(? patt) = (between 0 1 patt)
(1 patt) = (repeat 1 patt)
(2 patt) = (repeat 2 patt)
(3 patt) = (repeat 3 patt)
...
(opt patt) = (between 0 1 patt)
(quote patt ?tag) = (capture patt ?tag)
'patt = (capture patt)
Get basic help.
Usage: pdoc [option] [peg-special]
View Janet PEG information.
-h, --help show this output
-d, --doc [<peg-special>] show doc
-q, --quiz [<peg-special>] show quiz question
-u, --usage [<peg-special>] show usage
--bash-completion output bash-completion bits
--fish-completion output fish-completion bits
--zsh-completion output zsh-completion bits
--raw-all show all names for completion
With a peg-special, but no options, show docs and usages.
If any of "boolean", "dictionary", "integer", "string",
"struct", or "table" are specified as the "peg-special",
show docs and usages about using those as PEG constructs.
With the `-d` or `--doc` option, show docs for specified
PEG special, or if none specified, for a randomly chosen one.
With the `-q` or `--quiz` option, show quiz question for
specified PEG special, or if none specified, for a randomly
chosen one.
With the `-u` or `--usage` option, show usages for
specified PEG special, or if none specified, for a randomly
chosen one.
With no arguments, lists all PEG specials.
Be careful to quote shortnames (e.g. *, ->, >, <-, etc.)
appropriately so the shell doesn't process them in an
undesired fashion.
As a convenience feature, options (e.g. -u or -d) can be specified
before or after a PEG special, e.g. invoking:
pdoc -d thru
should yield the same result as:
pdoc thru -d
This was done so that quick editing of a previous command would be more convenient for different uses.
If interested in a particular PEG special, may be you'd prefer to be
invoking pdoc <peg-special> -d followed by pdoc <peg-special> -u,
and then may be even pdoc <peg-special> -q for a quiz question.
Instead, if interested in seeing usages for different PEG specials,
may be you'd prefer to be invoking pdoc -u int followed by
pdoc -u int-be or pdoc -u uint.
The PEG special argument to pdoc can be completed if using the bash
/ fish / zsh shells with appropriate configuration.
So for example, pressing TAB after entering pdoc a might yield the
output:
accumulate any argument at-least at-most
To set this up, invoke pdoc with one of the following for the
relevant shell:
--bash-completion--fish-completion--zsh-completion
Put the resulting output in a location appropriate for the shell in use. Something along the lines of:
-
bash- put output in file namedpdocin the directory at~/.local/share/bash-completion/complete/ -
fish- put output in file namedpdoc.fishin the directory at~/.config/fish/completions/ -
zsh- put output in file named_pdocand put it in a directory that's on yourfpath
Below are some links to resources that are probably much better than the bits above:
- bash --
look for
Where should I install my own local completions? - fish
- zsh -- good luck...just kidding, see this instead.
There is a macro named pdoc (a bit like the built in doc macro)
that can be used from the REPL to look up PEG special documentation.
One way to use it is to start janet like:
janet -l pegdoc
Then at the REPL:
Janet 1.32.1-11d7af3f linux/x64/gcc - '(doc)' for help
repl:1:> (pdoc if)
peg special
(if cond patt)
Tries to match patt only if cond matches as well.
cond will not produce any captures.
nil
Alternatively, evaluate (use pegdoc) before invoking (pdoc ...).
Setting up one's user profile appropriately may be another way to make
pdoc available (see -R and/or JANET_PROFILE info in the janet(1)
manual page for hints).
Like the doc macro, pdoc can also be invoked with a string (or no
argument) to produce a set of search results. The results are grouped
according to whether they are primitive, combining, or capture
patterns.
Portions of tests and the documentation come from Janet and the janet-lang.org website.
Thus the following license applies to at least those portions.
Copyright (c) 2019, 2020, 2021, 2022, 2023, 2024 Calvin Rose and contributors
Permission is hereby granted, free of charge, to any person obtaining a copy of
this software and associated documentation files (the "Software"), to deal in
the Software without restriction, including without limitation the rights to
use, copy, modify, merge, publish, distribute, sublicense, and/or sell copies
of the Software, and to permit persons to whom the Software is furnished to do
so, subject to the following conditions:
The above copyright notice and this permission notice shall be included in all
copies or substantial portions of the Software.
THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
SOFTWARE.