digitalmars.D.learn - Accessing members of an array of a class with map.
- Ave (45/45) Sep 30 2016 An example of what I'm trying to do:
- Jonathan M Davis via Digitalmars-d-learn (4/49) Sep 30 2016 The first example is segfaulting, because you never gave the variable, t...
- Ave (4/11) Sep 30 2016 Hah wow. Can't believe I even retyped that whole thing and didn't
An example of what I'm trying to do: import std.stdio; import std.container; import std.algorithm; class Aa { Array!B arrB; } class Bb { string name; } void main() { Aa test; auto c=new Bb; c.name="asdf"; test.arrB.insert(c); auto d=new Bb; d.name="1234"; test.arrB.insert(d); writeln(test.arrB[].map!(x=>x.name); } I was able to get this to compile,but it segfaults. If I do this however: import std.stdio; import std.container; import std.algorithm; class Bb { string name; } void main() { Array!B arrB; auto c=new Bb; c.name="asdf"; arrB.insert(c); auto d=new Bb; d.name="1234"; arrB.insert(d); writeln(arrB[].map!(x=>x.name); } It will compile and work without seg faulting. What am I doing wrong in my first case that's causing the program to seg fault?
Sep 30 2016
On Friday, September 30, 2016 19:04:11 Ave via Digitalmars-d-learn wrote:An example of what I'm trying to do: import std.stdio; import std.container; import std.algorithm; class Aa { Array!B arrB; } class Bb { string name; } void main() { Aa test; auto c=new Bb; c.name="asdf"; test.arrB.insert(c); auto d=new Bb; d.name="1234"; test.arrB.insert(d); writeln(test.arrB[].map!(x=>x.name); } I was able to get this to compile,but it segfaults. If I do this however: import std.stdio; import std.container; import std.algorithm; class Bb { string name; } void main() { Array!B arrB; auto c=new Bb; c.name="asdf"; arrB.insert(c); auto d=new Bb; d.name="1234"; arrB.insert(d); writeln(arrB[].map!(x=>x.name); } It will compile and work without seg faulting. What am I doing wrong in my first case that's causing the program to seg fault?The first example is segfaulting, because you never gave the variable, test, a value. It's null when you try and access its arrB member. - Jonathan M Davis
Sep 30 2016
On Friday, 30 September 2016 at 19:31:55 UTC, Jonathan M Davis wrote:On Friday, September 30, 2016 19:04:11 Ave via Digitalmars-d-learn wrote:Hah wow. Can't believe I even retyped that whole thing and didn't see it. Thanks.[...]The first example is segfaulting, because you never gave the variable, test, a value. It's null when you try and access its arrB member. - Jonathan M Davis
Sep 30 2016