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The joke has been going on for quite some time now - Lisp and related languages use Polish Notation everywhere. (The main benefit is that (R)PN is parenthesis-

The joke has been going on for quite some time now - Lisp and related languages use Polish Notation everywhere. (The main benefit is that (R)PN is parenthesis-free, so it makes it easier for a calculator to process expressions with multiple operators. The use in programming languages is nonexistent but to make clear that +, *, .. are just like any other function call, where you would naturally use polish notation.)

Scaevolus 13y ago
Not nonexistent-- there are many stack-oriented programming languages[1], of which Forth is the most famous. There's even a "Reverse Polish Lisp" on HP calculators! [1] http://en.wikipedia.org/wiki/List_of_programming_languages_by_type#Stack-based_languages http://en.wikipedia.org/wiki/List_of_programming_languages_b...
- revelation 13y ago
  Sorry, I meant there is no benefit to using it in programming languages.
  - Scaevolus 13y ago
    Forth is arguably the best language in terms of expressive power/language complexity, though that's largely due to the denominator. It's a great choice for tightly constrained devices, though far fewer devices have such constraints now. The mental overhead of having to track stack-effects for each function makes it difficult to scale to large systems and maintain productivity, but if you're trying to eke every iota of power out of a chip with a tiny amount of ROM, it's hard to beat a direct-threaded (or token-threaded...) Forth.
- nealabq 13y ago
  See also http://en.wikipedia.org/wiki/Reverse_Polish_notation#Current_implementations http://en.wikipedia.org/wiki/Reverse_Polish_notation#Current...
deleted 13y ago
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orclev 13y ago
> Lisp and related languages use Polish Notation everywhere. > The main benefit is that (R)PN is parenthesis-free ... so what you're saying is Lisp has all those parenthesis just to troll us? Seriously though, using PN can make implementing parsers a lot simpler as it makes the grammar less ambiguous.
- anaphor 13y ago
  I don't know about less ambiguous, it can still require only single token lookahead and be context-free without any parentheses, but Lisp-ish languages are easier to parse because you have fewer productions to worry about compared to more complex languages.

Scaevolus 13y ago

Not nonexistent-- there are many stack-oriented programming languages[1], of which Forth is the most famous. There's even a "Reverse Polish Lisp" on HP calculators! [1] http://en.wikipedia.org/wiki/List_of_programming_languages_by_type#Stack-based_languages http://en.wikipedia.org/wiki/List_of_programming_languages_b...

revelation 13y ago
Sorry, I meant there is no benefit to using it in programming languages.
- Scaevolus 13y ago
  Forth is arguably the best language in terms of expressive power/language complexity, though that's largely due to the denominator. It's a great choice for tightly constrained devices, though far fewer devices have such constraints now. The mental overhead of having to track stack-effects for each function makes it difficult to scale to large systems and maintain productivity, but if you're trying to eke every iota of power out of a chip with a tiny amount of ROM, it's hard to beat a direct-threaded (or token-threaded...) Forth.
nealabq 13y ago
See also http://en.wikipedia.org/wiki/Reverse_Polish_notation#Current_implementations http://en.wikipedia.org/wiki/Reverse_Polish_notation#Current...

deleted 13y ago

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orclev 13y ago

> Lisp and related languages use Polish Notation everywhere. > The main benefit is that (R)PN is parenthesis-free ... so what you're saying is Lisp has all those parenthesis just to troll us? Seriously though, using PN can make implementing parsers a lot simpler as it makes the grammar less ambiguous.

anaphor 13y ago
I don't know about less ambiguous, it can still require only single token lookahead and be context-free without any parentheses, but Lisp-ish languages are easier to parse because you have fewer productions to worry about compared to more complex languages.