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From: harp@pkg.mcc.com (Christopher North-Keys)
Newsgroups: comp.sys.sun
Subject: Re: nested ifs' in csh dont work?
Keywords: Software
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Date: 6 Jun 90 11:27:37 GMT
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They do indeed work, if the "if" in each instance in immediately followed
by a space, as already noted.  The only distinct oddness I've noted in Csh
programs is that aliases don't work placed in the format:

	if (cond) alias

where instead the following *must* be used:

	if (cond) then
		alias
	...

This type of thing also occurs in local variable setting.  There must be
spaces on *both* sides of the "=", or neither.  In contrast "=" is *not*
used in setenv commands.  It's worth noting that all local variables are
vectors (lists), and can easily be used as local stacks.

Nesting of if/then/else/endif, switch/case/breaksw/default/endsw,
while/break/end, etc., all works as expected.  The last person I found
having trouble was trying to use "break"/"end" in "switch", instead of the
required "breaksw"/"endsw".  He enclosed the entire switch in a "while 1 /
end" loop to get the misbegotten "break"/"end"s to do what he wanted.
This is called not reading the manual, folks.

I find the C shell flow constructs much more obvious than I do the Bourne.
The keyword "breaksw" is rather more intuitive than ";;".  But then, I'm a
C(++) programmer, and such were also the C shell authors :-).

Someone needs to write a nice, new (PD) shell from scratch, of course.
None of the existing shells are what I'd call either "consistent", or
"elegant" (personal opinion of: sh, ksh, csh, bash, tcsh).  In particular,
none of them support the loading of additional object modules at runtime,
nor state-dumping or the like (like GNUemacs) to reduce startup time.
Their command sets all require bizarre parsing (contrast to languages like
Lisp and Forth), and all have peculiarities.

------------------------------------/\----------------------------------------
Seo:  Harp[@Mcc.Com]               /  \/\ ^*^           Christopher North-Keys
Tha mi gu trang a'cluich.         /    \ \         Assoc. Systems Analyst, MCC
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