Warning: This is the manual of the legacy Guile 2.2 series. You may want to read the manual of the current stable series instead.

4.4.4 REPL Commands

The REPL exists to read expressions, evaluate them, and then print their results. But sometimes one wants to tell the REPL to evaluate an expression in a different way, or to do something else altogether. A user can affect the way the REPL works with a REPL command.

The previous section had an example of a command, in the form of ,option.

scheme@(guile-user)> ,option value-history #t

Commands are distinguished from expressions by their initial comma (‘,’). Since a comma cannot begin an expression in most languages, it is an effective indicator to the REPL that the following text forms a command, not an expression.

REPL commands are convenient because they are always there. Even if the current module doesn’t have a binding for pretty-print, one can always ,pretty-print.

The following sections document the various commands, grouped together by functionality. Many of the commands have abbreviations; see the online help (,help) for more information.