On Tue, Mar 25, 2014 at 4:28 PM, Steven D'Aprano <st...@pearwood.info> wrote: > On Tue, 25 Mar 2014 06:57:19 +1100, Chris Angelico wrote: > >> Can you imagine a high level language without a simple notation for >> variable assignment? Certainly not. > > I don't know... what a stack based or concatenative language like Forth, > Postscript, Joy or Factor count as high-level? > > I'm pretty sure Joy and Factor should. Perhaps not Forth or Postscript. > > Some of these language may offer variable assignment, but using it is > entirely optional. It's a convenience, nothing more.
Ah, sorry. I meant in languages that do have a concept of variable assignment. Yes, some don't have it at all, so of course they don't offer any notation for it. But any reasonably modern symbolic language is not going to have a long and wordy notation for assignment, because assignment is so common. It's language design Huffman coding: the features programmers are expected to use frequently are given convenient notations. A stack-based language will have extremely convenient notations for "push this onto the stack", something like "Put potatoes into the mixing bowl. Put dijon mustard into the mixing bowl. Put lard into the mixing bowl." (okay, so Chef might not be the best language to demonstrate this with!). A basic iterative for loop is considered extremely common. C has a highly compact notation that packs three parts into a simple header; REXX has a more piece-meal approach whereby "DO I=start" can be followed by any combination of "TO stop", "BY step", "WHILE condition", "UNTIL condition", and "FOR count", each of which has the same effect on its own or in combination with others. (I think WHILE and UNTIL might be incompatible with each other, but none of the others conflict. Having TO and FOR in the same loop header means it'll stop when either condition is reached.) And Python doesn't have any such construct, but *only* a 'foreach'. That's what I was talking about; and yet it works quite nicely. ChrisA -- https://mail.python.org/mailman/listinfo/python-list
