REPL mode

Version 1.1 added a REPL mode to Pip.

Basic usage

Run the interpreter with the -R flag to enter REPL mode.

Enter statements at the prompt to execute them. Entering an expression displays its repr. Incomplete statements/expressions can be continued on subsequent lines:

>> "Hello".
.. "world"
"Helloworld"
>> Fi\,3
.. Pi
1
2
3

The -R flag can be combined with certain other flags:

-w to display warnings (off by default)
List-formatting flags (only affects the str of a list; the repr is still used for displaying the results of top-level expressions)

REPL mode does not currently accept command-line arguments. Local variables a through g are all initialized to nil at top level (but can be assigned to, as usual).

REPL-specific features

The variables $_, $__, and $___ store the values of the last three top-level expressions:

>> 1
1
>> $_+1
2
>> [$_$__]
[2;1]

Certain comments are treated as REPL commands:

;warnings toggles display of warning messages (can also be invoked as ;warnings off or ;warnings on). The initial setting depends on whether the REPL was invoked with the -w flag or not.
;quit quits the REPL.
;exit is identical to ;quit.
;help displays a help message.

These commands can be abbreviated to any prefix of the command. For example, ;q works for ;quit, and ;warn off works for ;warnings off.

The REPL can also be exited via keyboard interrupt (usually Ctrl-C).