Should function argument be changed in function body?

[Chris Torek]

It has a much more obnoxious effect. If I <= LAST on entry it gives
an infinite loop and quite some UB. ;-).

Oops. Swap the first two quoted lines, yes. Also, the third line
should say "CALL COMPUT...", though of course this was really shorthand
for "some computation using X(I)".

(It has been at least 20 years since I wrote any Fortran, and even
then I used various RATFOR variants -- the one on BSD Unix, and
before that, the one I wrote for myself to use with Microsoft's
F80 on my TRS-80. Of course I had to write that one in Fortran.)

 

[Ed Prochak]

It is in some other, non-C languages:

SUBROUTINE FOO(X, I, LAST)
INTEGER I, LAST
REAL X(LAST)
IF (I .GT. LAST) GOTO 20
10 CONTINUE
COMPUT(X(I))
I = I + 1
GOTO 10
20 CONTINUE
RETURN
END

Here, this Fortran code has the obnoxious side effect of incrementing
the variable you call it with:

...
CALL FOO(ARR, I, 20)
C now I .EQ. 21

Perhaps some of the dogmatic "never modify a parameter" is left over
from old Fortran coders.

Chris, you've been writing C for() loops for too long. That function
NEVER returns! 8^)

Ed
(You need the 10 on the IF line.)

 

[Michael Wojcik]

You've peaked my curiosity,

Impressive. Most people's curiosity generally gets piqued; peaking it
requires something *really* curious.

on what implementations
(excluding the infamous DeathStation 9000) is a
size_t not defined as an 'unsigned int' ?

Well, most I32LP64 implementations, I imagine.

 

[CBFalconer]

Impressive. Most people's curiosity generally gets piqued;
peaking it requires something *really* curious.

I can see direct applicability to a PHB.

 

[pete]

Do you often have strings over 2GB long?

That has nothing to do with anything.

The only systems I know of
where it's likely to be too small in practical uses are a few 16 bit
ones.


Someone has to implement strlen...

Portable C is poor choice to implement a standard library function,
in a real implementation of the standard library.
length_of_string is supposed to be portable C, isn't it?

 

[Mark]

Impressive.

Thank you.

Most people's curiosity generally gets piqued;

peaked curiosity (googled) 85,300 hits
piqued curiosity (googled) 139,000 hits
I'll give you 'more' people... but not most

peaking it requires something *really* curious.

Are you sure about that?
peaked : To bring to a maximum of development, value, or intensity
pique : French, a prick, irritation, from Old French, from piquer, to prick,
from Vulgar Latin *piccre, ultimately of imitative origin.]

What??? Come on, a french prick irritation???
I guess what you call pique we call the clap!

Regards,
Mark