Difference between revisions of "Variable parameter"
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Variable parameter (or Reference Parameter) is input and output parameter | Variable parameter (or Reference Parameter) is input and output parameter | ||
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== Read more == | == Read more == | ||
− | * [ | + | * [http://lazarus-ccr.sourceforge.net/fpcdoc/ref/refsu48.html Variable parameter] |
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* [[Xor]] | * [[Xor]] | ||
* [[If]] | * [[If]] |
Revision as of 22:40, 18 March 2015
Variable parameter (or Reference Parameter) is input and output parameter meaning it can be used for passing a value to a function or a procedure as well as to get back a value from function or procedure. It indicated by the use of the keyword var in front of the formal parameter.
Variable parameter given a new nickname. The method refers to the same variable and changes made will affect the actual variable.
XOR swap
procedure XorSwap( var i,j:integer );
begin
i := i xor j ;
j := i xor j ;
i := i xor j ;
end;
OrderSmallBig
procedure OrderSmallBig( var a,b:integer );
begin
if a > b then XorSwap( a, b );
end;