How do I make word motions like w, b, and e treat hyphens or other characters as part of a word?

Explanation

By default, Vim treats hyphens, dots, and many punctuation characters as word boundaries. This means w, b, e, ciw, diw, and other word-based motions and text objects split on these characters. By modifying iskeyword, you can make Vim treat additional characters as part of a word, which is essential when working with CSS properties, Lisp identifiers, shell variables, or kebab-case naming conventions.

How it works

• :set iskeyword+=- — adds the hyphen to the set of keyword characters
• ciw on background-color now changes the entire hyphenated identifier instead of just background
• w jumps over my-variable-name as a single word instead of stopping at each hyphen
• Use :set iskeyword? to inspect the current value

Example

With default iskeyword, pressing ciw on the b in:

background-color: red;

Selects only background. After :set iskeyword+=-, ciw selects background-color.

Tips

• Add to a filetype-specific config: autocmd FileType css setlocal iskeyword+=-
• Add dots for Clojure/Lua namespaces: :set iskeyword+=.
• Use :set iskeyword& to reset to the default value
• W, B, E (uppercase) always use whitespace-only boundaries regardless of iskeyword