| Name | Type | Required | Default | Hint |
| predicate | string | true | A value that is truthy or falsy. |
Returns a passing (0) or failing (1) exit code if truthy parameter passed. Command outputs nothing.
Truthy values are "yes", "true" and positive integers.
All other values are considered falsey
assertTrue `package show private` && run-script foo
assertTrue ${ENABLE_DOOM} && run-doom
assertTrue `#fileExists foo.txt` && echo "it's there!"