Date comparsion bug

[vadjs]

a = new Date();
b = new Date(); 

a == b;  //false
a < b;  //false
a <= b;  //true  

This must be very strange mechanics.

[claudepache]

This is correct.

• a == b is false, because a and b are not the same Date object. It does not test whether they represent the same moment.
• On the other side, relational operators like < convert their operand to primitives before comparison. The primitive value of a Date object is the number of milliseconds since the epoch; so that they compare correctly the moments they represent.

The root issue is that == has different meanings according to the type of its operands (compares references for objects, compares values for primitives). This is unfixable. Use something more explicit than ==, e.g. a.valueOf() == b.valueOf().

[claudepache]

This is correct.

• a == b is false, because a and b are not the same Date object. It does not test whether they represent the same moment.
• On the other side, relational operators like < convert their operand to primitives before comparison. The primitive value of a Date object is the number of milliseconds since the epoch; so that they compare correctly the moments they represent.

The root issue is that == has different meanings according to the type of its operands (compares references for objects, compares values for primitives). This is unfixable. Use something more explicit than ==, e.g. a.valueOf() == b.valueOf().