Grammars for parsing and generating arbitrary strings, binaries, or other content in XO
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A grammar is the first step in parsing. It is used as a recognizer for some input sequence of symbols (utf-8 strings, binary, etc.). It then integrates with a generator which constructs output based on what it matches. The generators can be found in the content-ast-generator (for AST construction) or content-cst-generator (for syntax-highlighting) repos. Other types of generators can also be constructed, not just these two types.
The DSL is called the "match" DSL, for matching strings. There are 8 different types of match nodes:
sieve: What is nested inside of it is optional.chain: Matches one or more of the nested chunks.chunk: A chunk of patterns to match.crown: Pick the first one from the set to match.class: Delegate to a class to match.twist: Do not match this.check: Delegate to more sophisticated checks.write: Match a literal value.
Each match node is matched with match x, as in match chain... Each match node has "mounts", which are passing variables into it if necessary. A mount is like mount a, write 1, where the input name is a, and the value is 1.
You can also have shift nodes, for performing pure functions during parsing.
Finally, the start node is an input variable to the top-level match classes.
Here is a very basic example to demonstrate some of the nodes:
match x
match crown
match class, class a
match class, class b
match a
match write, write |a|
match b
match write, write |b(|
match sieve
match class, class x
match sieve
match chain
match write, write |,|
match class, class x
match write, write |)|
This should match any of these strings:
a
b()
b(a)
b(a,a)
b(b(b()))
b(a,b(a,a,b(),a,a))
All of these nodes get represented with the churn type. This is a generalized abstraction for representing all sorts of DSL which ultimately result in some processing.
Contributions are greatly welcomed. Identify the key painpoints in the customer onboarding flow, and help us map out the best solutions. See the contributor's guide for more info if you are just writeing out coding.
Copyright 2021 Mount
Licensed under the Apache License, Version 2.0 (the "License"); you may not use this file except in compliance with the License. You may obtain a copy of the License at
http://www.apache.org/licenses/LICENSE-2.0
Unless required by applicable law or agreed to in writing, software distributed under the License is distributed on an "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. See the License for the specific language governing permissions and limitations under the License.
Content grammar is being developed by the folks at Mount, a California-based project for helping humanity master information and computation. Mount started off in the winter of 2008 as a spark of an idea, to forming a company 10 years later in the winter of 2018, to a seed of a project just beginning its development phases. Mount funds start's development. It is entirely bootstrapped by working full time and running Etsy and Amazon shops. Also find us on Facebook, Twitter, and LinkedIn. Check out our other GitHub projects as well!