> Why would functions in a lisp-2 be more awkward than in a lisp-1? Jtsummers explained this quite well (as does the article). > PHP has been too long ago for

> Why would functions in a lisp-2 be more awkward than in a lisp-1? Jtsummers explained this quite well (as does the article). > PHP has been too long ago for me to understand your comparison. > Would you please explain it differently? PHP has a function namespace, which is used by C-style function definitions (similar to 'defun'): function foo(x) { return x; } and a separate value namespace, which is used by anonymous functions (similar to 'lambda'): $bar = function(x) { return x; }; Both sorts of function can usually[1] be called directly, e.g. foo(42); // Returns 42 $bar(42); // Returns 42 Passing around functions as values is tricky though. It's easy for the lambda-style values: array_map($bar, [0, 1, 2, 3]) For named functions, we have to provide a string containing the function's name, e.g.: array_map('foo', [0, 1, 2, 3]) This is very similar to the quoting of names in a lisp-2 (although using strings seems much uglier to me). [1] See https://news.ycombinator.com/item?id=8119419 https://news.ycombinator.com/item?id=8119419 for some (historical?) counterexamples