Tutorial 1: A minimalistic example¶
This tutorial shows a minimal example, the barely minimum what needs to be
written in order to get an Alice shell. The source files for this tutorial are
located in examples/tutorial1
.
#include <alice/alice.hpp>
ALICE_MAIN( tutorial1 )
That’s all! Two lines of code suffice. The first line includes the Alice
header alice/alice.hpp
. In all use cases, this will be the only header that
needs to be included. The second line calls ALICE_MAIN
, which takes as
argument a name for the shell. Besides acting as the prompt, it will also be
used as a name for the Python library, if it is build.
Compile tutorial1.cpp
and link it to the alice
interface library; have a
look into examples/CMakeLists.txt
to check the details. Even though we only
wrote two lines of code, we already can do several things with the program. When
executing the program (it will be in build/examples/tutorial1
), we can enter
some commands to the prompt:
tutorial1> help
General commands:
alias help quit set
It shows that the shell has 4 commands: alias
, help
, quit
, and
set
. Further information about each commands can be obtained by calling it
with the -h
flag. We’ll get to alias
later. Command help
lists all
available commands, and it also allows to search through the help texts of all
commands. Command quit
quits the program. Command set
can set
environment variables that can be used by other programs. Possible variables
and values are listed in the help strings to such commands.