Re: More on the cosmetics (if-statements)

From:

James Kanze <james.kanze@gmail.com>

Newsgroups:

comp.lang.c++

Date:

Fri, 01 Jun 2007 12:54:41 -0000

Message-ID:

<1180702481.526894.310220@o5g2000hsb.googlegroups.com>

On May 31, 3:01 pm, desktop <f...@sss.com> wrote:

terminator wrote:

On May 31, 3:13 pm, desktop <f...@sss.com> wrote:

Which would you prefer:

/* A */

        int k = 402;
        if ( k == 40) {
                std::cout << "40\n";
        } else {
                std::cout << "Not 40\n";
        }

/* B */
        if ( k == 40) std::cout << "40\n";
        else std::cout << "Not 40\n";

I know it depends on taste but I am just curious and would like to hear
your pro's and con's.

for the sake of maintanance and later correction/improvement 'A' is
better ;it prevents algorithmic errors due to later editing and
forggeting braces.

Ok but what about this (assuming that there is no such thing as a switch):

        int k = 40;

          /* Case 1. */
          if (k == 10) {
                  std::cout << "1\n";
          } else
                  /* Case 2. */
                  if (k == 20) {
                          std::cout << "2\n";
          } else
                  /* Case 3. */
                  if (k == 30) {
                          std::cout << "3\n";
          } else
                  /* Case 4. */
                  if (k == 40) {
                          std::cout << "4\n";
          }

Why the extra lines?
          if (k == 10) {
                  std::cout << "1\n";
          } else if (k == 20) {
                  std::cout << "2\n";
          } else if (k == 30) {
                  std::cout << "3\n";
          } else if (k == 40) {
                  std::cout << "4\n";
          }

/* INSTEAD OF:*/

          /* Case 1: Only 1 element in the list. */
          if (k == 10) {
                  std::cout << "1\n";
          } else {
                  if (k == 20) {
                          std::cout << "2\n";
                  } else {
                          if (k == 30) {
                                  std::cout << "3\n";
                          } else {
                                  if (k == 40) {
                                          std::cout << "4\n";
                                  }
                          }
                  }
          }

And why all the extra nesting. "else if" is pretty much a
recognized concept. Languages like Modula or Ada, which
force bracing the controled statements, almost always have an
elsif concept. C++ doesn't have it because it doesn't need
anything special to simulate the same construction.

--
James Kanze (GABI Software) email:james.kanze@gmail.com
Conseils en informatique orient=E9e objet/
Beratung in objektorientierter Datenverarbeitung
9 place S=E9mard, 78210 St.-Cyr-l'=C9cole, France, +33 (0)1 30 23 00 34