InstantFPC
Overview
This tool allows to run pascal program as scripts under Linux, BSD and OS X. For example:
<Delphi>
- !/usr/bin/env instantfpc
begin
writeln('Hello fpc user');
end. </Delphi>
Save the file as hello.pas, set the permission to execute and run it:
[]$ chmod a+x hello.pas []$ ./hello.pas Hello fpc user
Notes:
- The first line is called shebang and is stripped from the source before passing it to the compiler.
- The line 'program hello;' is optional in FPC. Because instantfpc passes the -o option to the compiler the line is ignored, so you can omit it.
Of course you can pass parameters to your script:
<Delphi>
- !/usr/bin/env instantfpc
var
i: Integer;
begin
for i:=0 to ParamCount do writeln(ParamStr(i));
end. </Delphi>
Save the file as params.pas, set the permission to execute and run it:
[]$ chmod a+x params.pas []$ ./params.pas A B /home/mattias/.cache/instantfpc/params.pas A B
Download
From svn
svn co https://lazarus-ccr.svn.sourceforge.net/svnroot/lazarus-ccr/applications/instantfpc instantfpc
Installation
- Compile the instantfpc.lpi with Lazarus or lazbuild. Or compile directly with fpc instantfpc.lpr.
- Put the executable into PATH, for example /usr/bin:
sudo cp instantfpc /usr/bin/
How it works
It uses a cache directory to compile. Default is $HOME/.cache/instantfpc. If HOME is not set it gives an error. You can override the directory by setting the environment variable INSTANTFPCCACHE. It compares the source with the stored file in cache and if it differs compiles the source, given the parameters in the shebang line (the first line of the script after #!). After successful compile it executes the program. If compilation fails it writes the fpc output to stdout.
Parameters
- -v: Print current version and exit
- --get-cache: Print current cache directory and exit
- -h: print help and exit
- -B: always compile even if cache is valid.
- --compiler=<path to compiler> use this compiler. By default fpc is searched in PATH.
Passing parameters to the compiler
Compiler parameters can be passed in the shebang line. But then you can not use the 'env' command.
<Delphi>
- !/usr/bin/instantfpc -O1 -Ci
begin end. </Delphi>
Editing in Lazarus
Since Lazarus 0.9.31 the IDE ignores the shebang line. You get all the normal code features.
Bugs / ToDos
- Changes to the compiler or installed units are not checked. If you install a new compiler you should clean the cache (e.g. delete the directory ~/.cache/instantfpc).
Alternatives
The following trick works in the bash. Put the program into a file fpc_script.sh:
<Delphi> // 2>/dev/null; fpc fpc_script.pp &> build.log && exec ./fpc_script "$@" || cat build.log; exit begin
writeln();
end. </Delphi>