One-liner Program

One-liner Program

A one-liner is textual input to the command-line of an operating system shell that performs some function in just one line of input.

The one liner can be

1. An expression written in the language of the shell.
2. The invocation of an interpreter together with program source for the interpreter to run.
3. The invocation of a compiler together with source to compile and instructions for executing the compiled program.

Certain dynamic scripting languages such as AWK, sed, and Perl have traditionally been adept at expressing one-liners. Specialist shell interpreters such as these Unix shells or the Windows PowerShell, allow for the construction of powerful one-liners.

The use of the phrase one-liner has been widened to also include program-source for any language that does something useful in one line.