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CPPstrings
D Strings vs C++ Strings
As I understood in example with D language you use dictionary which is realized with hash table. But in C++ example you use map which is realized with balanced trees. But hash table is faster than balanced trees.
Comments
In the section "Filling a String", shouldn't the D example use [2..3] instead of [1..3] ?
No, arrays are indexed from 0 so the second element is at 1. The slice is open on the end so [2..3] would just be str[2] = '?'.
A typo "All copy-on-write is is" -> "All copy-on-write [means] is".
In "Interoperability With C String Syntax", the second code sample is D and should be highlighted for D syntax.
These could be submitted as a bug: 
http://d.puremagic.com/issues/
Links
Corresponding page in the D Specification