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RascalShell commands


The RascalShell provides several built-in commands:

Next to these commands, the shell accepts all toplevel module Declarations, Statements and Expressions.


Here we just show some random shell commands:

rascal>int a = 0; // statement
int: 0
rascal>int f(int i) = 2 * i; // function declaration
int (int): function(|prompt:///|(0,21,<1,0>,<1,21>))
rascal>syntax Exp = Exp "+" Exp; // syntax declaration
rascal>f(2) * f(2) // expression
int: 16
rascal>:help // builtin command
Welcome to the Rascal command shell.

Shell commands:
:help Prints this message
:quit or EOF Quits the shell
:set <option> <expression> Sets an option
e.g. profiling true/false
tracing true/false
errors true/false
:edit <modulename> Opens an editor for that module
:test Runs all unit tests currently loaded

Example rascal statements and declarations:
1 + 1; Expressions simply print their output and (static) type
int a; Declarations allocate a name in the current scope
a = 1; Assignments store a value in a (optionally previously declared) variable
int a = 1; Declaration with initialization
import IO; Importing a module makes its public members available
println("Hello World") Function calling

Please read the manual for further information