let

Overview ¶

Package let implements the `let` shell built-in.

`let EXPR...` evaluates each arithmetic expression. The exit code is 0 if the last result is non-zero, 1 if it is zero (matching bash).

This is a self-contained mini arithmetic evaluator supporting integer arithmetic with +, -, *, /, %, parentheses, unary -, and simple assignments `name=expr`. Variables resolve through c.Env and assignments mutate c.Env. Expressions richer than this fall back to "0" and exit 1.