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digitalmars.D.learn - Casting classes

reply Jonathan Marler <johnnymarler gmail.com> writes:
How do casts work under the hood?  I'm mostly interested in what 
needs to be done in order to cast a class to a subclass.  I'd 
like to know what is being done to determine whether the object 
is a valid instance of the cast type.  If the code is implemented 
in the druntime, a pointer to where it lives would suffice.  
Thanks in advance for any help.
Jul 01 2016
parent reply Basile B. <b2.temp gmx.com> writes:
On Friday, 1 July 2016 at 15:45:35 UTC, Jonathan Marler wrote:
 How do casts work under the hood?  I'm mostly interested in 
 what needs to be done in order to cast a class to a subclass.  
 I'd like to know what is being done to determine whether the 
 object is a valid instance of the cast type.  If the code is 
 implemented in the druntime, a pointer to where it lives would 
 suffice.  Thanks in advance for any help.
https://github.com/dlang/druntime/blob/master/src/rt/cast_.d#L62 niptick: on github search then rather look at the results in the issues because in the code you'll get a lot of noise due to the unittests or like in this case because if the keywords. https://github.com/dlang/druntime/search?q=cast&type=Issues&utf8=%E2%9C%93
Jul 01 2016
parent reply Basile B. <b2.temp gmx.com> writes:
On Friday, 1 July 2016 at 17:32:26 UTC, Basile B. wrote:
 On Friday, 1 July 2016 at 15:45:35 UTC, Jonathan Marler wrote:
 How do casts work under the hood?  I'm mostly interested in 
 what needs to be done in order to cast a class to a subclass.  
 I'd like to know what is being done to determine whether the 
 object is a valid instance of the cast type.  If the code is 
 implemented in the druntime, a pointer to where it lives would 
 suffice.  Thanks in advance for any help.
https://github.com/dlang/druntime/blob/master/src/rt/cast_.d#L62 niptick
damn, where is the "edit" button ^^
Jul 01 2016
parent Jonathan Marler <johnnymarler gmail.com> writes:
On Friday, 1 July 2016 at 17:34:25 UTC, Basile B. wrote:
 On Friday, 1 July 2016 at 17:32:26 UTC, Basile B. wrote:
 On Friday, 1 July 2016 at 15:45:35 UTC, Jonathan Marler wrote:
 How do casts work under the hood?  I'm mostly interested in 
 what needs to be done in order to cast a class to a subclass.
  I'd like to know what is being done to determine whether the 
 object is a valid instance of the cast type.  If the code is 
 implemented in the druntime, a pointer to where it lives 
 would suffice.  Thanks in advance for any help.
https://github.com/dlang/druntime/blob/master/src/rt/cast_.d#L62 niptick
damn, where is the "edit" button ^^
You pointed me right to it! Thanks this is exactly what I was looking for. I figured it was doing something like this but now I have confirmation.
Jul 01 2016