> You can almost parse the expression with the same technique.

not really, for a syntax tree you would need an [OP, arg1, arg2] format.

this

["B", "'", "+", ["C", "*", "D"], "'"]]

doesn't help without further parsing because precedence is still not resolved.

Rather 

[ "or", 
    [ "not" , "B" ] , 
    [ "not", 
        [ "and", "C", "D"]
    ] 
]

[download]

without recursive parsing hard to achieve, I just delegated the hard part to Perl, deliberately ignoring what the OP didn't tell us yet.

edit

For instance if the = is not an assignment but a condition, he would want solutions for this equation system...

(which I could produce at least by brute force for small variable sets, if we had a guarantied format)

Cheers Rolf
(addicted to the Perl Programming Language and ☆☆☆☆ :)
Je suis Charlie!

In reply to Re^3: Parsing Boolean expressions (hack) by LanX
in thread Parsing Boolean expressions by Anonymous Monk

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