2 releases
0.1.1 | Oct 14, 2022 |
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0.1.0 | Apr 16, 2022 |
#1533 in Parser implementations
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SLoC
s-expr
Rust library for S-expression like parsing and printing
- parser keeps track of spans, and representation (e.g. number base)
- number and decimal don't limit size
- only 1 dependency on
unicode-xid
S-expressions features
Extra features which are not in usual s-expressions (cannot be turned off):
- binary and hexadecimal number, when starting a number with the prefixes respectively
0b
or0x
. _
characters in number, e.g.0xfedc__1240__abcd
or100_000_000
to improve legibility
Currently unsupported:
- symbol with spaces
- negative literal integral and decimal, currently
-123
will be tokenized as the ident-
followed by number123
. - scientific notation for decimal numbers
6.022e23
will be parsed as decimal6.022
then idente
, then number23
There's lots of variant of S-expression, so the parser allow to parse various different optional features that can be enabled/disabled depending on the user wishes:
- semi-colon line comment
- byte string of the format :
#8BADF00D#
- braces
{ }
and bracket[ ]
group, which behave like( )
but provide equivalent grouping balancing check and flavor of grouping