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maybe need a lint checker application program to preen basic programs?

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Not all bad program code gets caught at compile time;
but a really really comprehensive error checker would bog down the compiler badly.
A middle ground might be a  un*x-like   'lint'  program that one could run on their
production software source code as a final paranoid check, even if it runs all night.

Here's an example bad program that compiles cleanly

01 * {I know  nnnEnn   and nnnFnn  are scientific notation constants in some
02 *  other languages, but don't think they are part of basic}
03 *  But they generally won't be noticed as bad syntax at compile time...
04 *
05 *  Variable names are assumed to start with a letter;
06 *  numbers found before first variable on a line are assumed to be a
07 *  program label number, even without any ":" or space after the 'label'.
08 *
09 1E3 = 6    ;* compiler treats this as  1: E3 = 6   (that is, 1 is a label number)
10 crt 'e3 is ':E3 ;* sez  e3 is 6
11 *
12 *  alphabetic text after a numeric constant is presumed to be a mask expr
13 *  though I'm not sure what 'E3 + 4'  is supposed to mean in real life...
14 crt 1E3 + 4     ;* sez  10000.0
15 crt 2E3         ;* sez  2.000000
16 goto  7         ;* proves 7frog below is parsed as if it were 7: frog = 42
17 crt 'dead code' ;* does not get executed
18 7frog = 42
19 crt 'frog is ':frog ;* sez  frog is 42
20 stop
21 end

What features are worth putting in such a 'lint' program is highly debatable, but perhaps;

            (imperfectly, I'm sure) find variables that are used before being set,
                  (many basics give error msgs about that, but only at run time)
            variables set but never used {so that name was probably mis-typed by author}
             numeric  labels with neither space nor ":" after them
             suspicious-looking mask expressions {author left out an intended '+' 
operator}
                    and that is a very broad term, 'suspicious', hence elicits a huge 
block of
                     program logic.  Maybe just log a warning if that form not used in any 
other
                     certified-ok production programs in the same account, or if involves 
a
                     non-trivial variable name that is also used in a non-masking role in 
same prog?

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maybe need a lint checker application program to preen basic programs? "Frank Winans" <fwinans@sbcglobal.net> - 2015-07-31 14:08 -0500

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