Parsing/evaluating shortcutting operators

I have written a strongly typed BASIC compiler and virtual machine in
Javascript, just for the exercise in compiler writing and "behind the
scenes" insight of high level languages after coming from an assembly/C
background.


I decided use a basic stack machine for simplicity.


I am unsure how to proceed in setting up shortcutting operators
however. For example, this code:


declare boolean b


b = (1 == 2) || (3 == 4)


Which results in the expression
1 2 == 3 4 == || b =


And the opcodes of:
(calli calls an internal/library function)


push_int 1
push_int 2
calli_integer_compare
push_int 3
push_int 4
calli_integer_compare
calli boolean compare
push_var 1
calli boolean_assign


The only approach I can think of is to really mangle my source and turn it
into more like this pcode: (Variables beginning with t are temp
variables.)




t1 = 1 == 2
if !t1 { // False value, so go onto the next case.
    t1 = 2 == 3
}
b = t1


Is there a better approach?
Does someone have an example of a parser that handles shortcutting
operators that I can take a look at?
[Shortcut evaluation is really a shorthand for the if/else you discovered.
That's pretty much how you have to do it. -John]

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