How to get hash value of an object?

[panmengh via Digitalmars-d-learn]

How to get hash value of an object?

Use hashOf? or typeid(T).getHash(&o)?

I test with the following code:

System:
windows 10

dmd --version
DMD32 D Compiler v2.072.0 (official download version)

ldc2 --version
LDC - the LLVM D compiler (1.1.0git-62a2252) (the latest git 
master version)
   based on DMD v2.071.2 and LLVM 3.9.1git

import std.stdio;

void main()
{
     string[string] a;
     string[string] b0;

     writeln(a.hashOf(), "\t\t",typeid(typeof(a)).getHash(&a), 
"\t\t\t",
         b0.hashOf(), "\t\t",typeid(typeof(b0)).getHash(&b0), "  
", a,);

     a["1"] = "1";
     string[string] b1 = ["1":"1"];
     writeln(a.hashOf(), "\t\t",typeid(typeof(a)).getHash(&a), 
"\t\t",
         b1.hashOf(), "\t\t",typeid(typeof(b1)).getHash(&b1), "  
", a,);

     a["9"] = "9";
     string[string] b2 = ["1":"1", "9":"9"];
     writeln(a.hashOf(), "\t\t",typeid(typeof(a)).getHash(&a), 
"\t\t\t",
         b2.hashOf(), "\t\t",typeid(typeof(b2)).getHash(&b2), "  
", a,);

     a["3"] = "3";
     string[string] b3 = ["1":"1", "9":"9", "3":"3"];
     writeln(a.hashOf(), "\t\t",typeid(typeof(a)).getHash(&a), 
"\t\t",
         b3.hashOf(), "\t\t",typeid(typeof(b3)).getHash(&b3), "  
", a,);

     a.remove("1");
     a["1"] = "1";
     string[string] b4 = ["1":"1", "9":"9", "3":"3"];
     writeln(a.hashOf(), "\t\t",typeid(typeof(a)).getHash(&a), 
"\t\t",
         b3.hashOf(), "\t\t",typeid(typeof(b4)).getHash(&b4), "  
", a,);
}

Output:
dub --compiler=dmd -a=x86_64
Running .\test2.exe
1669671676      0           1669671676  0           []
732702303       2197205690  683765274   3388425732  ["1":"1"]
732702303       0           912895782   0           ["1":"1", 
"9":"9"]
732702303       2197205690  4139255736  3388425732  ["3":"3", 
"1":"1", "9":"9"]
732702303       2197205690  4139255736  3388425732  ["3":"3", 
"1":"1", "9":"9"]

test2.exe (second run)
1669671676      0           1669671676  0           []
1608602074      122060002   2487796584  31054674    ["1":"1"]
1608602074      0           3256818953  0           ["1":"1", 
"9":"9"]
1608602074      122060002   667025292   31054674    ["3":"3", 
"1":"1", "9":"9"]
1608602074      122060002   667025292   31054674    ["3":"3", 
"1":"1", "9":"9"]

dub --compiler=ldc2 -a=x86_64
Running .\test2.exe
593689054       0           593689054   0           []
1747365348      1899073920  1747365348  1899073920  ["1":"1"]
3252326176      0           3252326176  0           ["1":"1", 
"9":"9"]
492636279       1899073920  492636279   1899073920  ["3":"3", 
"1":"1", "9":"9"]
492636279       1899073920  492636279   1899073920  ["3":"3", 
"1":"1", "9":"9"]

test2.exe (second run)
593689054       0           593689054   0           []
1747365348      2353409518  1747365348  2353409518  ["1":"1"]
3252326176      0           3252326176  0           ["1":"1", 
"9":"9"]
492636279       2353409518  492636279   2353409518  ["3":"3", 
"1":"1", "9":"9"]
492636279       2353409518  492636279   2353409518  ["3":"3", 
"1":"1", "9":"9"]

Does only hashOf with ldc2 return the right value?