design & implement functions

[christianparpart]

Syntax Spec Proposal

functionDecl      ::= 'def' SYMBOL '(' functionParamDecl ')' ':' TYPE '=' expr
functionParamDecl ::= TYPE SYMBOL (',' TYPE SYMBOL)*
TYPE              ::= 'int' | 'bool' | 'string'

Example functions:

def fib(int n) : int = {
  if (n < 3)
    return 1;
  else
    return fib(n - 1) + fib(n - 2);
}

def sum_up(int n) : int = {
  if (n < 2)
    return n;
  else
    return sum_up(n - 1) + n;
}

Implementation Checklist

• AST
• syntax
• AST->IR transform
• IR extensions
• IR->TC codegen
• VM implementation