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> If by random access you mean constant time access then those developers would be very disappointed to learn that they cannot do that in Java, C#, C++, JavaScr

> If by random access you mean constant time access then those developers would be very disappointed to learn that they cannot do that in Java, C#, C++, JavaScript or Python, unless they happen to know that their string cannot possibly contain any characters outside the ASCII or BMP range. Actually, you can in Python... and obviously most developers ignore such issues [citation needed] My point is that most developers don't know these details, a lot of idioms are ingrained... get them to work with string types properly won't be easy (but a good stdlib would obviously help immensely in this regard) > I would leave indexing/slicing operators in place and make sure everyone knows that it works with bytes not codepoints. In addition to that I would provide an O(n) function to access the nth codepoint as part of the standard library. Ok, so with your proposal an hypothetical slicing method on a String class in a java-like language would have this signature? byte[] slice(int start, int end); I've been fancying the idea of writing a custom String type/protocol for clojure that deals with the shortcoming of Java's strings... I'll probably have a try with your idea as well :)

masklinn 13y ago
> Actually, you can in Python... No, you can only get random access on codepoints which will break text as soon as combining characters are involved. Even if you normalize everything beforehand (which most people don't do) as not all possible combinations have precomposed forms. Unicode makes random access useless at anything other than destroying text. > but a good stdlib would obviously help immensely in this regard Which is extremely rare, and which Python does not have.
fauigerzigerk 13y ago
>Actually, you can in Python You are right (apart from combining characters as masklinn explained), but as I said, that's only possible if an array of 32 bit ints is used to hold string data or if it can be guaranteed that there are no characters from outside ASCII or BMP. If I understand PEP 393 correctly, what Python 3.3 does is to use 32 bit ints to hold the entire string if even one such code point occurs. So if you load a (possibly large) text file into a string and one such code point exists then the file's size is going to quadruple in memory. All of that is done just to implement one very rare operation efficiently. http://www.python.org/dev/peps/pep-0393/#new-api http://www.python.org/dev/peps/pep-0393/#new-api

masklinn 13y ago

> Actually, you can in Python... No, you can only get random access on codepoints which will break text as soon as combining characters are involved. Even if you normalize everything beforehand (which most people don't do) as not all possible combinations have precomposed forms. Unicode makes random access useless at anything other than destroying text. > but a good stdlib would obviously help immensely in this regard Which is extremely rare, and which Python does not have.

fauigerzigerk 13y ago

>Actually, you can in Python You are right (apart from combining characters as masklinn explained), but as I said, that's only possible if an array of 32 bit ints is used to hold string data or if it can be guaranteed that there are no characters from outside ASCII or BMP. If I understand PEP 393 correctly, what Python 3.3 does is to use 32 bit ints to hold the entire string if even one such code point occurs. So if you load a (possibly large) text file into a string and one such code point exists then the file's size is going to quadruple in memory. All of that is done just to implement one very rare operation efficiently. http://www.python.org/dev/peps/pep-0393/#new-api http://www.python.org/dev/peps/pep-0393/#new-api