Opportunity

Jesse Phillips Jessekphillips+d at gmail.com
Tue Apr 9 19:30:41 PDT 2013


On Tuesday, 9 April 2013 at 16:54:30 UTC, Peter Alexander wrote:
> On Tuesday, 9 April 2013 at 15:50:11 UTC, Andrei Alexandrescu 
> wrote:
>> Lack of generics makes it very tenuous to do meaningful work 
>> on algorithms and their associated data structures.
>
> Why?

I think the answer to that is working on implementing an 
algorithm to work on a data structure not provided by the 
language can only reach as far as the type you implemented the 
algorithm for. Thus the work done to implement that algorithm 
wasn't very meaningful as it isn't reusable.

On a similar note. Earlier I was having a discussion with someone 
who was stating, "The problem with the whole generics complaint 
is that people tend to focus on Go's lack of generics to mean Go 
lacks any safe polymorphism at all." He was quite aware "What Go 
doesn't have is parametric polymorphism."

I was kind of worried that it would be impossible to specify a 
different sort for a data type. I ended up writing some code to 
sort a slice of Time[1]. I was glad to find out I was wrong, but 
also very concerned with what I did find.

1. http://ideone.com/eVWfnk

- There is a built in function make which takes a type! That was 
interesting.
- Data doesn't provide a default means to sort.
- I had to write the data access of the array!
- I also couldn't get the functions to take a slice of time, 
instead I had to define a TimeSlice which was a slice of time.

Needless to say WTF! That was with a built in data structure, at 
least I know it will work with any custom structure.


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