How the Glob Pattern Filter Works

Code2Prompt uses glob patterns to include or exclude files and directories, working similarly to tools like tree or grep. It lets you pass two independent lists of glob patterns:

• include list (--include or -i) - “these patterns allow files”
• exclude list (--exclude or -e) - “these patterns disallow files”

Code2prompt must decide, for every file in the project, whether it is kept or discarded. This page explains the rules, and the design choices behind them.

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1. Sets and Symbols

Throughout the explanation we use the usual set notation

Symbol	Meaning
	set of files that match at least one include pattern
	set of files that match at least one exclude pattern
	the whole project tree (the universe)
	files that match both lists (the overlap)
	files that match neither list

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2. Four Situations

Overview of the four situations

Include list	Exclude list	Files kept
A = ∅	B = ∅	Ω
A = ∅	B ≠ ∅	¬B
A ≠ ∅	B = ∅	A
A ≠ ∅	B ≠ ∅	A \ B

1. No include list, no exclude list

   If no patterns are specified, all files are kept (Ω).

2. Exclude list only

   In this case, Code2Prompt acts as a blacklist, removing files that match the excluded patterns ( Ω \ B = ¬B).

3. Include list only

   If only an include list is specified, Code2Prompt acts as a whitelist, keeping only files that match the included patterns (A).

4. Include and exclude lists

   If both lists are specified, Code2Prompt keeps files that match the include patterns, but removes those that match the exclude patterns (A \ B).

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3. More on the overlap

With both lists present (A ≠ ∅, B ≠ ∅) you have four logical possibilities for the overlap C and the rest D.

Want C?	Want D?	Reasonable?
No	No	Default behaviour (A \ B)
Yes	No	Same behavior as case 3 (A)
No	Yes	surprising (“discard what I asked for C, keep what I didn’t”)
Yes	Yes	Same behavior as case 1 (Ω)

This is for this reason that the --include-priority option was removed. Because, it would be the same result as if you had only an include list (case 3).

4. Quick reference table

Want to keep…	Use
everything	no -i, no -e
everything except some patterns	-e only
only what matches the patterns	-i only
what matches -i, minus what matches -e	-i and -e

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This design keeps the mental model simple:

• The include list is a whitelist as soon as it exists.
• The exclude list is a blacklist layered on top.
• The overlap is discarded by default