Here's a simple tool you can use to check whether you have one or more expected sets of contiguous integers in a file (or some other input).

$ pip install summarize-ranges

Works with Python 3.8 through 3.14.

• --tsv print TAB-separated high,low range values.
• --python print closed,open Python ranges.
• --ignore-word-boundaries (or --iwb) match numbers with no respect for word boundaries (e.g., match the 33 in abc33def).
• --ignore-negatives (or --in) do not match leading hyphens that would otherwise indicate a negative number. So catch-22 will result in the number 22 being collected rather than -22.

You can of course redirect a file or more complicated pipeline into summarize-ranges. The examples below all just use echo for simplicity.

# One range is found:
$ echo 3 | summarize-ranges
Range 1: 3

$ echo 3 4 5 | summarize-ranges
Range 1: 3 to 5

# TAB-separated output:
$ echo 3 4 5 | summarize-ranges --tsv
3	5

# TAB-separated output for Python:
$ echo 3 4 5 | summarize-ranges --tsv --python
3	6

# Two ranges:
$ echo 3 5 | summarize-ranges
Range 1: 3
Range 2: 5

$ echo some text 3 more 4 text and 6, 7, 8. | summarize-ranges
Range 1: 3 to 4
Range 2: 6 to 8

# Negative numbers are recognized:
$ echo some text -3 and -4. | summarize-ranges
Range 1: -4 to -3

# But leading hyphens in numbers can be ignored:
$ echo some text -3 and -4. | summarize-ranges --ignore-negatives
Range 1: 3 to 4

# Python style closed-open ranges
$ echo 3 | summarize-ranges --python
Range 1: 3 to 4

$ echo 3 4 5 10 11 | summarize-ranges --python
Range 1: 3 to 6
Range 2: 10 to 12

# Ignore word boundaries:
$ echo some33 text34here and 35. | summarize-ranges --ignore-word-boundaries
Range 1: 33 to 35

There is a simple Python class, RangeSummarizer you can use to build your own tools. See src/summarize_ranges/ranges.py and the tests in test/test_summarizer.py.

Testing is done with pytest and nox.

env PYTHONPATH=src pytest and nox can be used directly. Or, to use the Makefile, install uv, then make test or make nox.

• Allow for --expect high,low arguments and exit non-zero if the expected range(s) are not found. This could also have a --strict option to check that there are no additional unexpected ranges found and a --quiet option to suppress output (though /dev/null can just be used).