Re: 6502 illegal opcodes questions

[pausch@saaf.se (Paul Schlyter)]

In article <1149428957.970012.309990@y43g2000cwc.googlegroups.com>,
mdj <mdj.mdj@gmail.com> wrote:

> sicklittlemonkey wrote:
> 
>> Saving keypresses in the way LN describes can really waste brain cycles
>> elsewhere. Years ago I tired of the proclivity for programmers to
>> abbreviate into 3 letters even 4 letter words (etc), just to fit a
>> pattern. Those days are long gone for me, and today's IDEs it's easy
>> enough to type the first few letters then ctrl-space to complete the
>> rest.
> 
> The old formatting 'rule' of not exceeding 80 characters on a line has
> finally started to die, along with the terminals that encouraged it,
> which has helped things a great deal.

That old formatting rule originated with the 80-column punched cards.
Early terminals more or less mimiced punched cards, and of course the
80-character line limit was more or less hardwired into the terminal.

Some programming languages even had these formatting rules built-in.
In e.g. FORTRAN (up to FORTRAN-77), these rules had to be obeyed:

Column 1:      C or * marked the whole line as a comment
Columns 2-6:   Labels went here - 1-5 decimal digits
Column 7:      A non-space character here marked this line as a contination line
Columns 8-71:  The program statement went here
Columns 72-80: Comment - anything here was ignored by the compiler

If your line happened to be longer than 80 characters (impossible on a
punched card, but quite possible in a text file), the compiler considered
the excess characters to be a new line.

Having a long statement spill over into and beyond column 72 could have
"interesting" side effect: that text was truncated by the compiler.  So if
it was a variable name, that name was truncated.  Did this lead to an
"undefined variable" error?  Oh no -- FORTRAN had implicit variable
declarations, so the compiler merely created a new variable with the truncated
name as variable name.....

> I share your appreciation of IDE's abilities to autocomplete code - the
> productivity difference is enormous, but then the mental agility lost
> to not remembering API definitions anymore is a bit of a concern.
> 
> Matt

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