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From: 8halfan@airmail.cc
To: 9fans@9fans.net
Subject: [9fans] Plan 9's style(6) manual page
Date: Sat,  7 Apr 2018 19:00:37 +0300	[thread overview]
Message-ID: <731be915ba87d1709cedd619aac23c0f@airmail.cc> (raw)

Just an amateur C programmer looking for answers. My main inspirations
for code
style is K&R 2nd edition and I'm curious about the instructions in Plan
9's
style(6) manual page (for reference,
http://man.cat-v.org/plan_9/6/style). I've
tried to think about the motivations, but not everything is as clear as
it
seems.

Going through style(6):

> no white space before opening braces.
> no white space after the keywords `if', `for', `while', etc.

This is unique to Plan 9, it seems. I can't come up with a reason --
both BSD
and Linux style use whitespace, and K&R does too, while Plan 9 doesn't.
Why?

> no braces around single-line blocks (e.g., `if', `for', and `while'
> bodies).

Apologies, but I'll have to Go and do it anyway :)

> automatic variables (local variables inside a function) are never
> initialized at declaration.

Why not? In order to reduce visual clutter? It seems like this should be
handled
case-by-case: in some situations this just wastes lines:

	int foo;
	foo = 12;
	func("blah", &foo);

> follow the standard idioms: use `x < 0' not `0 > x', etc.

I'm guessing this is for consistency and more common coincidence with
the flow
of spoken language.

> don't write `!strcmp' (nor `!memcmp', etc.) nor `if(memcmp(a, b, c))';
> always
> explicitly compare the result of string or memory comparison with zero
> using a
> relational operator.

Was that a common programmer error? cmp functions should return 0 if the
arguments are identical. Smells like disaster in baking!

> and this is not an exhaustive list

Is there anything missing?

That's all. Thanks for your time.



             reply	other threads:[~2018-04-07 16:00 UTC|newest]

Thread overview: 8+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2018-04-07 16:00 8halfan [this message]
2018-04-07 17:47 ` Jules Merit
2018-04-07 17:59 ` Digby R.S. Tarvin
2018-04-07 19:11   ` hiro
2018-04-07 20:14 ` Ori Bernstein
2018-04-07 20:38   ` tlaronde
2018-04-07 20:42   ` Skip Tavakkolian
2018-04-08  4:38   ` Rob Ote

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