Differences

This shows you the differences between two versions of the page.

--- guides:programstyle:whitespace [2020/08/04 16:11] – [One line per statement in most cases.] wikiadmin
+++ guides:programstyle:whitespace [2024/07/25 15:01] (current) – external edit 127.0.0.1
@@ Line 26: / Line 26: @@
    * **vi**
      * In vi, add //set expandtab// to your .vi, .exrc, vimrc or other
+   * **nano**
+     * In nano, add //set tabstospaces// to your .nanorc file in your home directory.
+     * You can also set the size of the indentation with //set tabsize 4// (or whatever size you wish).
@@ Line 54: / Line 58: @@
 When possible, a statement should occupy a single line.
+An unacceptable example
+<code c++>
+x =  r
+    *cos(theta * M_PI/180)
+    *sin(phi * M_PI/180)
+</code>
+An exception to this rule occurs when a line becomes long and needs to be wrapped.  This frequently occurs in
+  * Functions with many parameters
+  * Output lines
+See the [[guides:programstyle:indentation|Indentation]] section for examples.
+A second exception occurs when declaring multiple variables of the same type.  Again, see [[guides:programstyle:indentation|Indentation]] section for examples.
 ==== Use blank lines to separate sections of code. ====
+Much like new paragraphs in English composition, blank line should be used to separate different thoughts.
+The following is an unacceptable use of blank lines
+<code c++>
+int max = 0,
+    min = 0,
+    num,
+    sum = 0,
+    i,
+    count;
+bool first = true;
+cin >> count;
+for(i = 0; i < count; i++) {
+    cin >> num;
+    if(first) {
+       min = num;
+       max=num;
+       first = false;
+    }
+    sum += num;
+    if (num > max) {
+       max = num;
+    }
+    if (num < min) {
+        num = min;
+    }
+}
+</code>
+The following is a more acceptable use of blank lines.
+<code c++>
+int max = 0,
+    min = 0,
+    num,
+    sum = 0,
+    i,
+    count;
+bool first = true;
+cin >> count;
+for(i = 0; i < count; i++) {
+    cin >> num;
+    if(first) {
+       min = num;
+       max=num;
+       first = false;
+    }
+    sum += num;
+    if (num > max) {
+       max = num;
+    }
+    if (num < min) {
+        num = min;
+    }
+}
+</code>
 ==== Consistently use a single style for brace placement. ====
+Braces are used to mark the body of control structures, type definitions and other related blocks of code.  A consistent use of bracket placement provides readers with a visual guide to the structure of a program.  There have been many styles ( see [[http://example.com|External Link|Wikipedia Article on Indentation Style]]) developed.
+Several styles are approved in the local style guide.
+=== Allman ===
+In the Allman style, braces associated with the start of a control statement begin on the next line, indented at the same level.
+<code c++>
+int main()
+{
+   int i;
+   bool printed = false;
+   for(i = 1; i < 100; i++)
+   {
+      printed = false;
+      if (i % 3 == 0)
+      {
+           cout << "fizz";
+           printed = true;
+      }
+      if (i % 5 == 0)
+      {
+           cout << "buzz";
+           printed = true;
+      }
+      if (not printed)
+      {
+           cout << i;
+      }
+      cout << endl;
+   }
+   return 0;
+}
+</code>
+=== K&R OTBS ===
+In this style, the opening brace is placed at the end of the beginning of a control structure.
+<code c++>
+int main() {
+   int i;
+   bool printed = false;
+   for(i = 1; i < 100; i++) {
+      printed = false;
+      if (i % 3 == 0) {
+           cout << "fizz";
+           printed = true;
+      }
+      if (i % 5 == 0) {
+           cout << "buzz";
+           printed = true;
+      }
+      if (not printed) {
+           cout << i;
+      }
+      cout << endl;
+   }
+   return 0;
+}
+</code>
+While either style is acceptable, programmers should select a single style and employ it constantly.
 ==== Place spaces between operators in statements. ====
-==== Do not exceed 80 characters for any line. ====
+Proper spacing in statements, especially mathematical calculations make it easier to read these statements.
+Unacceptable example:
+<code c++>
+for(i=0;i<20;i++) {
+    ...
+}
+x = r*cos(theta)*sin(phi);
+r1 = (-b+sqrt(4*a*c))/(2*a);
+</code>
+Acceptable example:
+<code c++>
+for(i = 0; i < 20; i++) {
+    ...
+}
+x = r * cos(theta) * sin(phi);
+r1 = (-b + sqrt(4*a*c)) / (2*a);
+</code>