Getting started

Lets try

Gufo is both a language with its own syntax and a shell system.

It tries to do a lot of pre-execution controls to only allow valid execution.

It uses the ‘%’ symbol as a start of prompt.

To start, just type ‘1 + 1’

% 1 + 1
2

The result ‘2’ appears, showing than everything went fine.

You can do a second trivial operation ‘1.4 + 1.6’, you will not be surprized much by the result:

% 1.4 + 1.6
3.000000

You can also call an external program, such as ‘ls’ or ‘pwd’ (or every available external program):

% pwd
/home/fpierre/Gufo

% ls
_build  configure  docs  exemples  guforun.native  LICENSE  Makefile  _oasis  opam  README.md  setup.data  setup.log  setup.ml  src  testKeyboard  THANKS.md  TODO.md

If you type something invalid, you will be warned before the executions of the command:

% 1 + "toto"
Expression do not have a common type: int  and: string

You can also use variables:

% let $a = 5

% let $b = $a * 10

% $b
50

Functionnality overwiew

• Inference type system and variable coloration depending of type.
• Pre-execution alerts.
• completion (using ‘tab’ key).
• variables and functions in a fonctional way.
• history (use arrows key to find previous expression).
• research (using CTRL + R).