• Running the REPL
• Variables
• Expression Statements
• Multi-line Input
• Line Editing

Running the REPL

Running the Pyro binary without a script argument launches the REPL — an interactive environment where you can run Pyro statements directly, e.g.

>>> echo "hello world";
hello world

Pyro statements normally end with a semicolon, ;, but you can omit the semicolon after typing a single statement in the REPL, e.g.

>>> echo "hello world"
hello world

Hit Ctrl-D or type exit and hit return to end the REPL session.

Variables

You can define and use variables in the REPL, just like in a script, e.g.

>>> var value = 123
>>> echo value + 456
579

Expression Statements

As a convenience, if the input statement is an expression that evaluates to any value other than null, the REPL automatically prints the $debug() string for the value, e.g.

>>> "foo" + "bar"
"foobar"

This is equivalent to running:

>>> echo $debug("foo" + "bar")
"foobar"

Multi-line Input

The REPL automatically handles multi-line input, e.g.

>>> "foo
··· bar"
"foo\nbar"

You can define functions and classes over multiple lines, e.g.

>>> def add(a, b) {
···     return a + b;
··· }
>>> add(1, 2)
3

Line Editing

The REPL supports the standard set of emacs-style line editing commands, e.g. Ctrl-A to move to the start of the line, Ctrl-E to move to the end of the line, etc.

You can scroll backwards and forwards through the line-editing history using the up/down arrow keys or, alternatively, Ctrl-P and Ctrl-N.