https://github.com/diogok/py_matching_pattern

Simplified dynamic pattern matching for python
https://github.com/diogok/py_matching_pattern

Last synced: about 2 months ago
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Simplified dynamic pattern matching for python

• Host: GitHub
• URL: https://github.com/diogok/py_matching_pattern
• Owner: diogok
• Created: 2019-12-04T11:31:09.000Z (about 5 years ago)
• Default Branch: master
• Last Pushed: 2020-01-11T16:40:14.000Z (almost 5 years ago)
• Last Synced: 2024-10-31T13:06:42.205Z (2 months ago)
• Language: Python
• Size: 7.81 KB
• Stars: 0
• Watchers: 2
• Forks: 0
• Open Issues: 0
• Metadata Files:
  • Readme: README.md

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README

        
# Python Pattern Matching

Inspired by [pampy](https://github.com/santinic/pampy) and [core.match](https://github.com/clojure/core.match), this is a pattern matching library for dynamic list of patterns.

Right now it only supports matching lists of same sizes.

## Usage

Import the lib

```python

import PatternMatchStore from py_matching_pattern

```

First you will add initialize a `PatternMatchStore` with a fixed size of keys to match (size of the list).

```python

pmdb = PatternMatchStore(keysize=3)

```

After that you can add the patterns. Every value is valid match, including `None`.

The "catch all" value is `default` attribute of the instance.

```python

_ = pmdb.default

pmdb.put(keys=["a","b","c"],value=1)

pmdb.put(keys=["a","b","b"],value=2)

pmdb.put(keys=["a","b",_],value=3)

pmdb.put(keys=["a",_,_],value=4)

pmdb.put(keys=["a",None,"c"],value=5)

pmdb.put(keys=["a",_,"d"],value=6)

```

These patterns are staged for the DB. This is useful if you reload the patterns from another thread.

To make the pattern live, you commit it.

```python

pmdb.commit()

```

Now you can finally start matching values:

```python

pmdb.get(keys=["a","b","c"])==1

pmdb.get(keys=["a","b","b"])==2

pmdb.get(keys=["a","b","d"])==3

pmdb.get(keys=["a","c","d"])==4

pmdb.get(keys=["a",None,"c"])==5

pmdb.get(keys=["a","e","d"])==6

pmdb.get(keys=["e","e","e"])==None

```

The staged patterns are kept between commits, so you can add or override to it later.

But in case you want to clean it:

```python

pmdb.clean()

```

It can also raise an exception if not found, but by default it will return `None`:

```python

pmdb = core.PatternMatchStore(keysize=3,raise_on_notfound=True)

pmdb.get(keys=["e","e","e"]) # raise KeyNotFound

```

## License

MIT