Re: [your code here]

[Jos van Uden]

On 15-1-2012 17:26, Timon Gehr wrote:

On 01/15/2012 03:23 PM, Jos van Uden wrote:

import std.conv, std.traits, std.ascii;

S rot13(S)(S s) if (isSomeString!S) {
return rot(s, 13);
}

S rot(S)(S s, int key) if (isSomeString!S) {
dchar[] r = new dchar[s.length];

foreach (i, dchar c; s) {
if (isLower(c))
c = ((c - 'a' + key) % 26 + 'a');
else if (isUpper(c))
c = ((c - 'A' + key) % 26 + 'A');
r[i] = c;
}
return to!S(r);
}


---

still learning this stuff, feel free to correct or improve

Jos

Your code will fail for narrow strings containing Unicode.
dchar[] r = new dchar[s.length]; // creates a new dchar[] with as many
elements as there are code units in the input string

You can use std.range.walkLength to get the number of code points.

Furthermore, that line mentions the type twice.

auto r = new dchar[s.walkLength()];

Thank you.

---

S rot13(S)(S s) if (isSomeString!S) {
    return rot(s, 13);
}

S rot(S)(S s, int key) if (isSomeString!S) {
    auto r = new dchar[s.walkLength()];

    foreach (i, dchar c; s) {
        if (isLower(c))
            r[i] = ((c - 'a' + key) % 26 + 'a');
        else if (isUpper(c))
            r[i] = ((c - 'A' + key) % 26 + 'A');
    }
    return to!S(r);
}