py-range-parse

py-range-parse is a library to parse commonly used range notations to python objects that act like sets.

py-range-parse is used by

• container-app-conf

and hopefully many others :)

How to use

pip install py-range-parse

from py_range_parse import parse_range

range = parse_range("[0..5]")

or create on manually:

from py_range_parse import Range
range = Range(0,5)

Input formats

When parsing a Range from a str any whitespace is ignored.

int ranges

If both the start and end value are of type int, the resulting Range will only consider integers as part of it. If you want to include float values as well, at least one of the values has to be a float.

• [-2 .. 5]
• [10 .. 1]

If the end value is bigger than the start value the resulting range will automatically be inverted. Therefore range.start <= range.end is always True in a Range.

float ranges

A float Range includes every possible float value between the start and end value.

• [-2.2 .. 5.123]
• [-2.0 .. 5]

Infinity

Infinity can also be specified using both inf as well as the unicode symbol ∞. Since it is internally represented using math.inf it will behave like a float.

• ]-inf .. inf[
• ]-∞ .. ∞[

Exclude borders

The start and end values can be excluded from the Range independent of one another using the open bracket notation.

• ]0 .. 5.5]
• ]0 .. inf[

Operations

Contains

You can easily check if a value is within a given Range like this:

> from py_range_parse import parse_range
> range = parse_range("[0 .. 5]")
> print(4 in range)
True

Comparison

You can check if a value is above or below a given Range using > and < respectively:

> from py_range_parse import parse_range
> range = parse_range("[0 .. 5]")
> print(6 > range)
True
> print(3 > range)
False
> print(3 < range)
False
> print(-1 < range)
True

Equality

You can compare equality of two Range instances using the == operator. For two ranges to be equal they have to have the same

• start value
• end value
• start inclusion
• end inclusion
• type (int or float)

> from py_range_parse import parse_range
> range1 = parse_range("[0 .. 5]")
> range2 = parse_range("[0 .. 5]")
> range3 = parse_range("[0 .. 5.0]")
> print(range1 == range2)
True
> print(range1 == range3)
False

Contributing

GitHub is for social coding: if you want to write code, I encourage contributions through pull requests from forks of this repository. Create GitHub tickets for bugs and new features and comment on the ones that you are interested in.

License

py-range-parse
Copyright (c) 2019 Markus Ressel

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.