simplematch 1.1

Minimal, super readable string pattern matching.

simplematch

Minimal, super readable string pattern matching for python.

import simplematch

simplematch.match("He* {planet}!", "Hello World!")
>>> {"planet": "World"}

simplematch.match("It* {temp:float}°C *", "It's -10.2°C outside!")
>>> {"temp": -10.2}

Installation

pip install simplematch

Syntax

simplematch has only two syntax elements:

• wildcard *
• capture group {name}

Capture groups can be named ({name}), unnamed ({}) and typed ({name:float}).

The following types are available:

• int
• float
• email
• url
• ipv4
• ipv6
• bitcoin
• ssn (social security number)
• ccard (matches Visa, MasterCard, American Express, Diners Club, Discover, JCB)

For now, only named capture groups can be typed.

Then use one of these functions:

import simplematch

simplematch.match(pattern, string) # -> returns a dict
simplematch.test(pattern, string)  # -> return True / False

Or use a Matcher object:

import simplematch as sm

matcher = sm.Matcher(pattern)

matcher.match(string) # -> returns a dict
matcher.test(string)  # -> returns True / False
matcher.regex         # -> shows the generated regex

Basic usage

import simplematch as sm

# extracting data
sm.match(
    pattern="Invoice_*_{year}_{month}_{day}.pdf",
    string="Invoice_RE2321_2021_01_15.pdf")
>>> {"year": "2021", "month": "01", "day": "15"}

# test match only
sm.test("ABC-{value:int}", "ABC-13")
>>> True

Type hints

import simplematch as sm

matcher = sm.Matcher("{year:int}-{month:int}: {value:float}")

# extracting data
matcher.match("2021-01: -12.786")
>>> {"year": 2021, "month": 1, "value": -12.786}

# month is no integer, no match
matcher.match("2021-AB: Hello")
>>> {}

# no extraction, only test for match
matcher.test("1234-01: 123.123")
>>> True

# show generated regular expression
matcher.regex
>>> '^(?P<year>[+-]?[0-9]+)\\-(?P<month>[+-]?[0-9]+):\\ (?P<value>[+-]?(?:[0-9]*[.])?[0-9]+)$'

Background

simplematch aims to fill a gap between parsing with str.split() and regular expressions. It should be as simple as possible, fast and stable.

The simplematch syntax is transpiled to regular expressions under the hood, so matching performance should be just as good.

I hope you get some good use out of this!

Contributions

Contributions are welcome! Just submit a PR and maybe get in touch with me via email before big changes.

License

MIT