CODEWITHSUNDEEP
delphi
Grandpa3D
Grandpa3D

Reputation: 13

How does this repeat … until 0 ≠ 0 loop terminate?

I ran across this piece of Borland Pascal code. I am curious as to how this does not repeat endlessly.

repeat
  if xs>(torgx+xlim)
    then begin
      x:=xlim;
      BREAK;
    end;

  if xs<(torgx-xlim)
    then begin
      x:=0-xlim;
      BREAK;
    end;

  x:=xs-torgx;
  BREAK;
until 0<>0;

I am confused as to how zero would ever be greater than or less than zero.

Upvotes: 1

Views: 83

Answers (1)

LU RD
LU RD

Reputation: 34949

A loop that continues until 0 <> 0 is supposed to be endless. But inside the loop there are some conditions that will break the loop, hence the use of the keyword break.

In fact, the repeat..until loop will only run once. The comparison is made that if a value is larger than a condition or less than another it will break out of the loop. If none of those conditions are met, it will break anyway.

Upvotes: 2

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