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0 pointskevin_thibedeau10y ago0 comments

Its not so disturbing when you consider that braces aren't special cased in the C grammar. They group statements so they can be used together where a statement is needed. From the grammar's perspective the "normal" way is without braces. It's just that all the C-alikes have gone a different direction with the way braces are parsed leading everyone to regard the original behavior in C as ugly warts.

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tmuir10y ago

for, if, and while without curly braces for single statement blocks are easily one of the worst things about C. It bites you in the ass every time. The balance between its utility and its capacity to cause bugs is so one sided, I don't understand why it's even taught to beginners. If you are teaching a new programmer that saving keystrokes is important, you're on the fast track to creating a shitty programmer.

JoeAltmaier10y ago

That's pretty severe. Written with spacing, its really pretty clear what is meant by

   if (condition)
      Foo(x)

Braces are, in my opinion, an unfortunate necessity in some cases. They are a much larger cause of error than NOT using them ever could be.

An ideal IDE would make blocking visible (background tone change etc), and braces could be emitted automatically by the IDE without ever cluttering up the code shown to the programmer.

tmuir10y ago

But tying everyone to a single IDE is never going to happen. The language is out there. It's going to stay backward compatible forever.

How could the presence of braces cause a worse error than no braces? Code compiles when you completely omit braces but put more than one statement underneath. The error is logical, not syntactical.

But if you have an open brace without a matching close brace, that's a compile error. What other error are you referring to?

How can you know that you won't add more statements to the block? Why have a special case at all? For me it's just become muscle memory to add the braces. It's a risk with exactly zero upside to omit braces.

Igglyboo10y ago

The only problem with this is if/when someone comes along and doesn't notice the missing braces and does

   if (condition)
      Foo(x)
      Bar(x)

Expecting Bar(x) to be part of the conditional. This can and does happen.

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gumby10y ago

non-bracket is useful and informative in some cases when used properly (your local style guide takes precedence of course). I would never write

   if (condition)
      Foo(x)

for the reasons you said. But it can be very useful for a block of "single liners":

  /* clean up input before passing it to flaky_external_module() */

  for(; !isspace(*p); ++p); 
  if (!isdigit(*p)) return INPUT_ERR;
  for (char *i = p; *i; i++) *i = toupper(*i);
  ...

  flaky_external_module(p);

Basically a small block (that pretty much fits in your fovea) that does a bunch of minor tasks. Spacing them out would actually confuse the code.

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tmuir10y ago

JoeAltmaier10y ago

That's pretty severe. Written with spacing, its really pretty clear what is meant by

   if (condition)
      Foo(x)

Braces are, in my opinion, an unfortunate necessity in some cases. They are a much larger cause of error than NOT using them ever could be.

An ideal IDE would make blocking visible (background tone change etc), and braces could be emitted automatically by the IDE without ever cluttering up the code shown to the programmer.

tmuir10y ago

But tying everyone to a single IDE is never going to happen. The language is out there. It's going to stay backward compatible forever.

How could the presence of braces cause a worse error than no braces? Code compiles when you completely omit braces but put more than one statement underneath. The error is logical, not syntactical.

But if you have an open brace without a matching close brace, that's a compile error. What other error are you referring to?

Igglyboo10y ago

The only problem with this is if/when someone comes along and doesn't notice the missing braces and does

   if (condition)
      Foo(x)
      Bar(x)

Expecting Bar(x) to be part of the conditional. This can and does happen.

1 more reply

gumby10y ago

non-bracket is useful and informative in some cases when used properly (your local style guide takes precedence of course). I would never write

   if (condition)
      Foo(x)

for the reasons you said. But it can be very useful for a block of "single liners":

  /* clean up input before passing it to flaky_external_module() */

  for(; !isspace(*p); ++p); 
  if (!isdigit(*p)) return INPUT_ERR;
  for (char *i = p; *i; i++) *i = toupper(*i);
  ...

  flaky_external_module(p);

Basically a small block (that pretty much fits in your fovea) that does a bunch of minor tasks. Spacing them out would actually confuse the code.

1 more reply

j / k navigate · click thread line to collapse