Why “=” operator results True when comparing varEmpty with a zero evalued varInteger?
Why does the = operator results True when comparing a varEmpty Variant variable with a zero evalued varInteger Variant variable?
var
V1 : Variant;
V2 : Variant;
begin
V2 := 0;
if(V1 = V2)
then ShowMessage('V1 = V2')
else ShowMessage('V1 <> V2');
end;
This code produces the following output:
V1 = V2
Does the equality operator = only checks the value part of Variant variables?
delphi operators delphi-2007 variant
asked Dec 27 at 13:42
Fabrizio
2,71331944
add a comment |
Why does the = operator results True when comparing a varEmpty Variant variable with a zero evalued varInteger Variant variable?
var
V1 : Variant;
V2 : Variant;
begin
V2 := 0;
if(V1 = V2)
then ShowMessage('V1 = V2')
else ShowMessage('V1 <> V2');
end;
This code produces the following output:
V1 = V2
Does the equality operator = only checks the value part of Variant variables?
delphi operators delphi-2007 variant
asked Dec 27 at 13:42
Fabrizio
2,71331944
add a comment |
Why does the = operator results True when comparing a varEmpty Variant variable with a zero evalued varInteger Variant variable?
var
V1 : Variant;
V2 : Variant;
begin
V2 := 0;
if(V1 = V2)
then ShowMessage('V1 = V2')
else ShowMessage('V1 <> V2');
end;
This code produces the following output:
V1 = V2
Does the equality operator = only checks the value part of Variant variables?
delphi operators delphi-2007 variant
asked Dec 27 at 13:42
Fabrizio
2,71331944
Why does the = operator results True when comparing a varEmpty Variant variable with a zero evalued varInteger Variant variable?
var
V1 : Variant;
V2 : Variant;
begin
V2 := 0;
if(V1 = V2)
then ShowMessage('V1 = V2')
else ShowMessage('V1 <> V2');
end;
This code produces the following output:
V1 = V2
Does the equality operator = only checks the value part of Variant variables?
delphi operators delphi-2007 variant
delphi operators delphi-2007 variant
asked Dec 27 at 13:42
Fabrizio
2,71331944
asked Dec 27 at 13:42
Fabrizio
2,71331944
asked Dec 27 at 13:42
Fabrizio
2,71331944
asked Dec 27 at 13:42
Fabrizio
2,71331944
asked Dec 27 at 13:42
Fabrizio
2,71331944
2,71331944
add a comment |
add a comment |
1 Answer
1
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oldest
votes
In order to make a comparison, the empty variant is converted to an integer. According to the variant type conversion rules, the unassigned (empty) variant is converted to 0. Hence the expression returns true.
answered Dec 27 at 15:01
Sertac Akyuz
47.9k371127
add a comment |
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1 Answer
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1 Answer
1
active
oldest
votes
active
oldest
votes
active
oldest
votes
In order to make a comparison, the empty variant is converted to an integer. According to the variant type conversion rules, the unassigned (empty) variant is converted to 0. Hence the expression returns true.
answered Dec 27 at 15:01
Sertac Akyuz
47.9k371127
add a comment |
In order to make a comparison, the empty variant is converted to an integer. According to the variant type conversion rules, the unassigned (empty) variant is converted to 0. Hence the expression returns true.
answered Dec 27 at 15:01
Sertac Akyuz
47.9k371127
add a comment |
In order to make a comparison, the empty variant is converted to an integer. According to the variant type conversion rules, the unassigned (empty) variant is converted to 0. Hence the expression returns true.
answered Dec 27 at 15:01
Sertac Akyuz
47.9k371127
In order to make a comparison, the empty variant is converted to an integer. According to the variant type conversion rules, the unassigned (empty) variant is converted to 0. Hence the expression returns true.
answered Dec 27 at 15:01
Sertac Akyuz
47.9k371127
answered Dec 27 at 15:01
Sertac Akyuz
47.9k371127
answered Dec 27 at 15:01
Sertac Akyuz
47.9k371127
answered Dec 27 at 15:01
Sertac Akyuz
47.9k371127
47.9k371127
add a comment |
add a comment |
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