DIBOL and RPG for RSTS
bfranchuk at jetnet.ab.ca
Sun Mar 29 01:20:49 CDT 2020
On 3/28/2020 7:06 PM, dwight via cctalk wrote:
> RPN is just there to simplify the interpreter and compiler. It takes some getting used to. Many claim that infixed is more natural but it is clumsy. One has to come up with a bunch of rules to make work.
> A + B * C
> multiply B and C an then add A.
> C B * A + in Forth
> Telling someone to do the calculation:
> Take C and B, multiply them together then take A and add it. ( how unnatural is that )
> What if A B and C were not numbers but instead were function and procedures that returned values. Lets say C turned on a light and returned the current used. B multiplied it by the line voltage and A was a previous Watt total.
> Would you still write it like the first, knowing it would get the right result because of some order rule?
> Of course, in Forth you'd never use A B and C for such names but you could if you never expected anyone to read it. ( I've seen Forth look like that )
> In Forth you always do things left to right. It is much less error prone. Well written Forth looks like sentences where you are telling the computer what to do and in what order. Good high level code rarely has SWAP or ROT in it.
> I had a friend that was tasked with writing code to do one of the error correction routines.
> He wrote it in Forth and gave it to his manager.
> His manager said "There must be a mistake, you have given me the definition of the code. Where is the code?"
> What better complement could a programmer get. I always
ive to get to that level.
I feel that Fig-Forth was the best of all the Forth's out there, Other
Forth's kept changing too much from what I felt was a good standard for
16 bit stuff.
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