terminology/DEV.md

Double Width

The code to decide whether a unicode codepoint should be rendered double-width is generated from the Unicode specification. This is done by using tools/unicode_dbl_width.py.

1. Download https://www.unicode.org/Public/UCD/latest/ucdxml/ucd.all.flat.zip
2. Extract it
3. Run tools/unicode_dbl_width.py ucd.all.flat.xml src/bin/termptydbl.h src/bin/termptydbl.c_
4. Commit the files modified