::SHE+ILA:: Enumerators and Lookups [$20]

More about ::SHE+ILA:: Enumerators and Lookups [$20]

Consider the initializer :
rainbow <:: (red=$F00, orange=$F80, yellow=$FF0, green=$0F0, cyan=$0FF, blue=$00F, violet=$F0F);
This creates a two row Buffer (table), whose first row is the symbol table :
rainbow[0] .eq. ("red", "orange", "yellow", "green", "cyan", "blue", "violet");
and whose second row is the corresponding VGA colours :
rainbow[1] .eq. ($F00, $F80, $FF0, $0F0, $0FF, $00F, $F0F);
This can be used as both an "enum" (as in C++) an as a lookup table. For example, let's get the name of the second colour :
ttyout rainbow[0][2]; // This prints "orange"
Now let's get its VGA RGB value :
ttyout .hex. rainbow[1][2]; // This prints $0F80
Now let's get the enum position of "orange" :
ttyout rainbow[0] .lookup. "orange";
This prints 2 :)
If the entire initialiser is the first line of a function definition, we can also say :
ttyout .hex. orange; // Again printing $0F80, the "value" of the local variable orange.