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ALT TypeScript code defining a Port type that accepts 1 to 65535, digit by digit, using template literal types. listen(3000) and listen(65535) compile, while listen(65536) and listen(0) are underlined in red as errors.
ALT TypeScript code: a Username template literal type built from 3 required one-character placeholders and 5 optional ones, so only strings of 3 to 8 characters are allowed. "dan" and "danfry" compile; "df" (too short) and "danfrydev" (too long) are errors.
ALT TypeScript code: a Username template literal type built from 3 required one-character placeholders and 5 optional ones, so only strings of 3 to 8 characters are allowed. "dan" and "danfry" compile; "df" (too short) and "danfrydev" (too long) are errors.
ALT TypeScript code defining a NonEmptyString type that only accepts strings with at least one character, without using branded types or `any`. The example assigns a normal string successfully, then shows an empty string assignment marked as a type error. Below, a Zod schema builds the same rule at runtime with z.string().refine(...), checking that the string length is greater than zero and returning the message string must contain at least one character.
