Convert Spaces to Tabs

By default, only leading spaces (indentation at the start of lines) are converted. Spaces within lines, in strings, or for alignment are preserved. This targets indentation style without affecting code content.

Lines with partial indentation (e.g., 6 spaces with 4-space tabs) can be handled different ways: convert what aligns with tab stops, round to nearest, or preserve partial spacing. Choose based on whether the irregularity is intentional.

The make utility was designed in 1976 to require tabs for recipe lines. This wasn't considered problematic then, but now causes frequent issues. Make will fail with "missing separator" errors if spaces are used instead of tabs.

For most languages, indentation with tabs works identically to spaces. Python is sensitive to consistent indentation—don't mix tabs and spaces within a file. The conversion should be all-or-nothing for Python code.

Count the spaces used for one level of indentation in your file. Common values are 2 or 4 spaces per indent level. Set the conversion width to match so each indent level becomes exactly one tab.