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Forum Index : Microcontroller and PC projects : To Space or Not To Space
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Geoffg Guru  Joined: 06/06/2011 Location: AustraliaPosts: 3194 |
Following the posting regarding MMBasic 3.1 there was some discussion regarding spaces and, as Gizmo said, it should have its own topic. The subject of spaces is not straight forward. In the earlier BASICS with one character variable names spaces were not required at all. This is a section from a real program (superstartrek.bas): 8680 IFS8=1THENQ$=A$+RIGHT$(Q$,189):RETURN
8690 IFS8=190THENQ$=LEFT$(Q$,189)+A$:RETURN 8700 Q$=LEFT$(Q$,S8-1)+A$+RIGHT$(Q$,190-S8):RETURN With 32 character variable names, defined subroutines, etc you need spaces so that the interpreter can find where components of the program start and finish. The C language goes even further and you can insert spaces almost everywhere. For example, this is valid: a = function ( arg1 , arg2 );
I try not to invent new standards where there is already an established standard so I have tried to follow MS BASIC with the use of spaces. The other factor is that MMBasic does have a problem with figuring out syntax errors and responding intelligently to them. I found it very hard when the interpreter is in the depths of decoding a PRINT statement to issue an useful error message. This could be part of the frustration related to spaces - all you get is a syntax error when the interpreter could have figured where a space should or should not have been. Ah well, another version I guess :-) Geoff Geoff Graham - http://geoffg.net |
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djuqa Guru Joined: 23/11/2011 Location: AustraliaPosts: 447 |
Fair enough While we are on the subject of new version/features maybe need to start/re-start a WISHLIST VK4MU MicroController Units |
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Gizmo Admin Group  Joined: 05/06/2004 Location: AustraliaPosts: 5078 |
I like to keep the opening bracket next to the command, it's what I've always seen and used, and makes it easier for me to read the line of code, because it keeps the command and its variables grouped together. for example PRINT #1, left$(A$,5);
is easier to follow. We are are going to print, to port #1, a string. PRINT #1, left$ (A$,5);
is harder to follow, the space between the left$ and ( in the 2nd example break up the flow, its like 2 separate things are happening. We're going to print, to port #1, a command with no data, some data by itself. I think its just personal experience, I read and write code every day as my job and I'm used to seeing commands next to their brackets, and I use spaces to separate the different commands. When you get into other languages spaces become very important, a space between the command and the ( would cause an error. I would not like to see MMBasic inserting spaces, but I think it could be OK if it ignored spaces, providing this doesnt cause a problem with commands that expect spaces. Glenn The best time to plant a tree was twenty years ago, the second best time is right now. JAQ |
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Nick Guru Joined: 09/06/2011 Location: AustraliaPosts: 512 |
I agree. I personally like a space after some commands. FOR X =1 TO 100 is neater than FORX=1TO100 But some commands look better without. PIXEL(10,10) MID$(10,A$). I remember avoiding all spaces back in the 80's as a way to gain speed. It saved some cycles if the interpreter didn't have to locate and skip spaces. Likewise for multi statement lines. Speed was important when writing a realtime game in BASIC, especially when your CPU was only clocked at 2MHZ. Not so much of a problem nowadays. Modern programmers have it so much easier. 
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| djuqa Guru Joined: 23/11/2011 Location: AustraliaPosts: 447 |
Yes I can still remember using my first SERIOUS High Level language Compiler on CPM-80. CBasic by Digital Research 1/ Start compilation 2/ Get up and put on kettle for coffee 3/ Realise some Mongrel had used the last of it. 4/ Hop in car & drive 2 Blocks to shop 5/ Stop at Newsagent and buy Byte magazine 6/ Arrive back at office 7/ Chat up secretary. 8/ Make the coffee. 9/ Go back to desk And I still had to wait until compile had finished. Typically compilation of the Multi-user inventory package took 1 hour 40 minutes. VK4MU MicroController Units |
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| Nick Guru Joined: 09/06/2011 Location: AustraliaPosts: 512 |
CPM-80?? Ohh! You had a disk drive!  |
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| djuqa Guru Joined: 23/11/2011 Location: AustraliaPosts: 447 |
It had a shugart 5mb hard drive and 2 * 8inch floppies 256mb ram card (that cost 5500$) Z80a cpu card all in a S100 box custom built by myself. Terminal was an old DEC ex Qld. Uni. cbasic was a totally different dialect of basic to microsoft it had problems with spaces as well as weird syntax So why did we use it? IT WAS the FAST execution speed VK4MU MicroController Units |
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TassyJim Guru Joined: 07/08/2011 Location: AustraliaPosts: 6098 |
As an ex Queenslander, I would treat FORX as a variable. It is that time of the day...... Jim VK7JH MMedit MMBasic Help |
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crackerjack Senior Member  Joined: 11/07/2011 Location: AustraliaPosts: 164 |
Space is what is used up by posts which often, but not always, end up comparing how hard it was way back, when one of the posters used to program by waving magnets over a flake of lodestone while the other space consumer (not invader) reflects on how tricky it was to balance a stack of parchment punch cards that had been laboriously drilled through with a blunt stick and which contained an algorithm to add two positive whole numbers in the range of 1 to 5.
As far as significant whitespace in MMBasic, it could become quite tricky to deal with. Spaces, Tabs, Carriage Returns, Linefeeds and numerous other "invisible" characters are best left out of having syntactic meaningfulness or there is a risk of the language becoming esoteric. I understand the difficulties this poses to interpreters and compilers and even more so to the developers thereof. So far I think Geoff (and other contributors) have done a great job of allowing the flexibility there is regarding spaces in MMBasic |
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| TassyJim Guru Joined: 07/08/2011 Location: AustraliaPosts: 6098 |
You young chaps all had it easy. My Uni days were: Type up the punch cards Hand them in to the clerk in the basement. Come back the next day to get your printout. Fortran of course. (C was still a few years away) Jim VK7JH MMedit MMBasic Help |
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| djuqa Guru Joined: 23/11/2011 Location: AustraliaPosts: 447 |
For x = coldbeer to drink VK4MU MicroController Units |
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