Auto-decoding

[ag0aep6g via Digitalmars-d-learn]

On 07/15/2017 06:21 AM, bauss wrote:
> I understand what it is and how it works, but I don't understand 
> anything of how it solves any problems?
> 
> Could someone give an example of when auto-decoding actually is useful 
> in contrast to not using it?

1) Drop two elements from "Bär". With auto-decoding you get "r", which 
is nice. Without auto-decoding you get [0xA4, 'r'] where 0xA4 is the 
second half of the encoding of 'ä'. You have to know your Unicode to 
understand what is going on there.

2) Search for 'ä' (one wchar/dchar) in the `string` "Bär". With 
auto-decoding, you pop the 'B' and then there's your 'ä'. Without 
auto-decoding, you can't find 'ä', because "Bär" doesn't have a single 
element that matches 'ä'. You have to search for "ä" (two `char`s) instead.

The goal of auto-decoding was to make it so that you don't have to think 
about Unicode all the time when processing strings. Instead you could 
think in terms of "characters". But auto-decoding falls flat on that 
goal, which is why it's disliked. You still have to think about Unicode 
stuff for correctness (combining characters, graphemes), and now you 
also have to worry about the performance of auto-decoding.