Stdlib function should be able to exit the process

[Mte90]

Discussing on #339

We saw that some function like create_symbolic_link can fails if the file is not found but also show a warning to the user.
We are wondering:

• The developer should be able to turn off this warnings in the code generated
• We want that those cases exit/close the process/script?
  • This is a common behavior because in Bash instead the process will continue if the developer doens't do some checks

[CymDeveloppement]

maybe developper (or user by --verbose option) can set a verbosity level and activate/deactivate info, warning, error echo
0 succes and error only
1 succes, warning, error
2 succes, info, warning, error

[Mte90]

PHP as something similar and also Python so the idea is not bad at all.

Like on top of the Amber script:

set_behaviour(1);

• 0 (default): Shows warnings/error and exit if the stdlib function fails
• 1: Shows only warning/errors

I think that the default should be 0. In this way the developers are forced to check what they are doing it if they want a different behavior but a script as default will close it instead proceed like other scripting language does.

[CymDeveloppement]

i think automatic exit comportement and warning display must be separated.
for me is 2 different problem

[CymDeveloppement]

maybe if a faillable function has no failed block, we can implement a default failed block failed{ exit(1) }

[Mte90]

This is another interesting solution, now that there is #300 can open to new features for the compiler.