let doesn't return the numeric value of the expression as an exit code: > If the last ARG evaluates to 0, let returns 1; let returns 0 otherwise. Which allows

let doesn't return the numeric value of the expression as an exit code: > If the last ARG evaluates to 0, let returns 1; let returns 0 otherwise. Which allows you to do things like: while let --i; do some command; done or if let x > 4; then some command; fi