Shrinking JS: the Ternary
When the wire format is text, code size is cost — reach for the ternary.
published Aug 10, 2017 tags
#javascript
#minification
~/posts/minify-ternary $ cat post.md
JS is shipped (and largely executed) as text, so the first lever for making it smaller is just writing fewer characters. The ternary operator pulls disproportionate weight here.
Take this:
let a = 10;
if (a === 10) {
return 123;
} else {
return 456;
}Six lines, plenty of characters. A slightly tighter version:
let a = 10;
if (a === 10) return 123;
else return 456;The semicolon after
return 123;is not optional.
Fewer lines, but return shows up twice; I also prefer not to drop JS
semicolons unless I have solid test coverage.
The ternary form:
let a = 10;
return a === 10 ? 123 : 456;One line. Same intent, less to read.
Hand-minification like this only goes so far. For real size savings on a build artifact, lean on a tool like uglify or terser — beyond the scope here.