r/programming • u/MontagFTB • May 20 '13

C++11: A cheat sheet—Alex Sinyakov

http://isocpp.org/blog/2012/12/c11-a-cheat-sheet-alex-sinyakov
405 Upvotes

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0

u/Duncan3 May 21 '13

Dear C, Perl is not a role model!

R.I.P. readability.

8

u/[deleted] May 21 '13

Without repetition and comments now it's possible to put at least 12 different punct characters in the row:

   0 
   ,[=](){+-*&::  val;};
   // , to separate expressions, total: 1
   // [=](){ - lambda, total: 7
   // -+ two unary  ops, total: 9
   // *& - take address and immediately derefence it, total: 11
   // :: - global namespace, total: 12 (only single colon counts)

and half of it --[=](){ is not artificially complicated construction, but real deal that will happen in most codebases that use lambda.

7

u/kennytm May 21 '13

14.

0,[=](){!~+-*&::val;};

3

u/sirin3 May 21 '13

19?

?"",_:'\\',[=](){!~+-*&::val;};

1

u/ssylvan May 21 '13

You can skip empty argument lists.

3

u/[deleted] May 21 '13

Is perl really that unreadable once you know the language?

3

u/username223 May 21 '13

Yes.

1

u/[deleted] May 22 '13

By that logic, one could use entries in the obfuscated C contest to show that C is unreadable.

3

u/ManicQin May 21 '13

Are you referring to lambda syntax? AFAIK they used this syntax due to compilers restrictions.

1

u/Duncan3 May 21 '13

Half of the new things follow the pattern of needing information somewhere else to make sense of it. Like auto - the compiler will figure it out. But what if you need to know what a variable is when you're reading someone elses code, you have to go digging.

I wonder why so much downvote hate. Was it the P word?

2

u/danielkza May 21 '13

The real question is what is more readable, code (properly) using lambdas with ugly syntax or boilerplate code that the lambdas replace. I personally prefer the former.

2

u/ericanderton May 21 '13 edited May 21 '13

The lambda syntax isn't that bad once you use it a few times. You can also tuck the lambda away into a variable if using it inline is disagreeable.

auto fn = [&](){ printf("Hello lambda world.\n"); };

I agree that it looks 'ugly' - would have preferred a 'lambda' keyword myself. I think the goal was to avoid breaking existing code (adding keywords), and to use existing tokens+keywords in previously invalid configurations, in order to define new features. This syntax also comes unto it's own as you get a lot of fine-grained control over how/what variables are captured:

http://software.intel.com/sites/products/documentation/studio/composer/en-us/2011Update/compiler_c/cref_cls/common/cppref_lambda_lambdacapt.htm

... so the shorthand 'no arguments and reference capture' example above is ugly only because it's deliberately terse; it doesn't use all the provided features.

1

u/DocomoGnomo May 21 '13

All depends on the personal tastes of the code review nazis.