6. Fanp
Overview
The fanp command line tool is used to dissemble compiled fcode. If you have a burning desire to hack the compiler or the runtime emit code, then you will find fanp indispensable. Like many of the other command line tools you can pass a pod name, a type qname, or a slot qname:
fanp fansh fanp fansh::Main fanp fansh::Main.main
By default only high level signatures and facets are printed. Print the usage via "-?" to see various options.
Dissembling Code
The "-c" option will dump the opcodes:
// fansh::Main.main
static Void main() { Shell.make.run }
// disassemble it
C:\>fanp -c fansh::Main.main
main () -> sys::Void [const public static]
[Code]
0: CallNew fansh::Shell.make() -> sys::Void
3: CallVirtual fansh::Shell.run() -> sys::Void
6: Return
[LineNumber] size=2
168
Dissembling Scripts
You can print the dissembled code of a script file after it is compiled but before it is executed using the "-fcodeDump" argument after the script filename:
fan script.fan -fcodeDump script.fan -fcodeDump // if script.fan is directly executable