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Revision as of 22:03, 17 September 2016

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→‎{{header|C}}: Fixed the worst of the C errors. This is not the competition page for the ugliest code.
m (→‎{{header|REXX}}: added/changed comments and whitespace, changed indentations.)
(→‎{{header|C}}: Fixed the worst of the C errors. This is not the competition page for the ugliest code.)
Line 88:
Demonstrating function scope as well as goto in a C program invariably leads to code like the one below. The [http://en.wikipedia.org/wiki/Scope_(computer_science)#C Wikipedia article] is a good starting point.
 
<lang C>/* Abhishek Ghosh, 8th November 2013, Rotterdam */▼
<lang C>▼
#include <stdio.h>▼
▲/*Abhishek Ghosh, 8th November 2013, Rotterdam*/
▲#include<stdio.h>
 
#define sqr(x) ((x) * (x))
#define greet printf("\nHelloHello There !\n");
 
int twice(int x)
{
return 2 * x;
}
 
int main(void)
{
int x;
 
printf("\nThisThis will demonstrate function and label scopes.\n");
printf("\nAllAll output is happening throung printf(), a function declared in the header file stdio.h, which is external to this program.\n");
printf("\nEnterEnter a number : ");
if (scanf("%d", &x); != 1)
return 0;▼
switch (x % 2) {
default:
default:printf("\nCaseCase labels in switch statements have scope local to the switch block.\n");
case 0: printf("\nYou entered an even number.");▼
case 0:
printf("\nIt's square is %d, which was computed by a macro. It has global scope within the program file.",sqr(x));▼
▲ case 0: printf("\nYouYou entered an even number.\n");
break;▼
▲ printf("\nIt'sIts square is %d, which was computed by a macro. It has global scope within the programtranslation fileunit.\n", sqr(x));
case 1: printf("\nYou entered an odd number.");
▲ break;
goto sayhello;
case 1:
jumpin: printf("\n2 times %d is %d, which was computed by a function defined in this file. It has global scope within the program file.",x,twice(x));▼
printf("\nSinceYou youentered jumpedan in,odd you will now be greeted, again !number.\n");
goto sayhello: greet;
jumpin:
if(x==-1)goto scram; ▼
▲ jumpin: printf("\n22 times %d is %d, which was computed by a function defined in this file. It has global scope within the programtranslation fileunit.\n", x, twice(x));
break;▼
printf("Since you jumped in, you will now be greeted, again!\n");
};
sayhello:
greet;
printf("\nWe now come to goto, it's extremely powerful but it's also prone to misuse. It's use is discouraged and it wasn't even adopted by Java and later languages.");▼
if (x == -1)
▲ if(x==-1)goto scram;
if(x!=-1){▼
▲ break;
x = -1; /*To break goto infinite loop.*/▼
}
goto jumpin;
 
}
▲ printf("\nWeWe now come to goto, it's extremely powerful but it's also prone to misuse. It'sIts use is discouraged and it wasn't even adopted by Java and later languages.\n");
 
scram: printf("\nIf you are trying to figure out what happened, you now understand goto.");▼
▲ if (x != -1) {
▲ return 0;
▲ x = -1; /* To break goto infinite loop. */
}
goto jumpin;
}
</lang>
 
scram:
▲ scram: printf("\nIfIf you are trying to figure out what happened, you now understand goto.\n");
return 0;
▲}</lang C>
 
{{out}} Example run:
<pre>
This will demonstrate function and label scopes.
All output is happening throung printf(), a function declared in the header file stdio.h, which is external to this program.
Enter a number : 5
 
You entered an odd number.
Hello There !
We now come to goto, it's extremely powerful but it's also prone to misuse. It'sIts use is discouraged and it wasn't even adopted by Java and later languages.
2 times -1 is -2, which was computed by a function defined in this file. It has global scope within the programtranslation fileunit.
Since you jumped in, you will now be greeted, again !
Hello There !
If you are trying to figure out what happened, you now understand goto.
</pre>
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