On Sunday, 8 June 2014 at 01:44:27 UTC, Jonathan M Davis via
Digitalmars-d-learn wrote:
On Sat, 07 Jun 2014 20:53:02 +0000
Paul via Digitalmars-d-learn
<digitalmars-d-learn@puremagic.com> wrote:
I can not understand, why this code works:
char s[2] = ['0', 'A'];
string ss = to!string(s);
writeln(parse!uint(ss, 16));
but this can deduces template:
char s[2] = ['0', 'A'];
writeln(parse!uint(to!string(s), 16));
What's the reason? And what is the right way to parse
char[2]->int with radix?
std.conv.to converts the entire string at once. std.conv.parse
takes the
beginning of the string until it finds whitespace, and converts
that first
part of the string. And because it does that, it takes the
string by ref so
that it's able to actually pop the elements that it's
converting off of the
front of the string, leaving the rest of the string behind to
potentially be
parsed as something else, whereas because std.conv.to converts
the whole
string, it doesn't need to take its argument by ref.
So, what's causing you trouble you up is the ref, because if a
parameter is a
ref parameter, then it only accepts lvalues, so you have to
pass it an actual
variable, not the result of to!string. Also,
string s = ['A', '0'];
will compile, so you don't need to use to!string in this case.
- Jonathan M Davis
Tnank you very much!!
