c# 4.0 - Conflicting overloaded methods with optional parameters -

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i have 2 overloaded methods, 1 optional parameter. 

void foo(string a)  { }   void foo(string a, int b = 0) { }

now call:

 foo("abc");

interestingly first overload called. why not second overload optional value set zero?

to honest, have expect compiler bring error, @ least warning avoid unintentional execution of wrong method.

what's reason behaviour? why did c# team define way?

from msdn:

if 2 candidates judged equally good, preference goes candidate not have optional parameters arguments omitted in call. consequence of general preference in overload resolution candidates have fewer parameters.


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