This code
import std.conv;
import std.stdio;
void main()
{
auto str = "123 456.7 false";
auto i = parse!int(str);
auto d = parse!double(str);
auto b = parse!bool(str);
assert(i == 123);
assert(d == 456.7);
assert(b == false);
}
results in this exception when you run it
std.conv.ConvException@std/conv.d(2654): Can't parse string: bool should be case-insensive 'true' or 'false'
----------------
./q(bool std.conv.parse!(bool, immutable(char)[]).parse(ref immutable(char)[])+0x183) [0x43867b]
./q(_Dmain+0x42) [0x430ec2]
./q(extern (C) int rt.dmain2.main(int, char**).void runMain()+0x1c) [0x43b240]
./q(extern (C) int rt.dmain2.main(int, char**).void tryExec(scope void delegate())+0x2a) [0x43abba]
./q(extern (C) int rt.dmain2.main(int, char**).void runAll()+0x3b) [0x43b287]
./q(extern (C) int rt.dmain2.main(int, char**).void tryExec(scope void delegate())+0x2a) [0x43abba]
./q(main+0xd1) [0x43ab45]
/usr/lib/libc.so.6(__libc_start_main+0xf5) [0x7fd238fc1725]
----------------
If you change it to
import std.conv;
import std.stdio;
void main()
{
auto str = "false 123 456.7";
auto b = parse!bool(str);
auto i = parse!int(str);
auto d = parse!double(str);
assert(i == 123);
assert(d == 456.7);
assert(b == false);
}
you get
std.conv.ConvException@std/conv.d(1771): Unexpected ' ' when converting from type string to type int
----------------
./q(int std.conv.parse!(int, immutable(char)[]).parse(ref immutable(char)[])+0x1b8) [0x431984]
./q(_Dmain+0x33) [0x430eb3]
./q(extern (C) int rt.dmain2.main(int, char**).void runMain()+0x1c) [0x43b240]
./q(extern (C) int rt.dmain2.main(int, char**).void tryExec(scope void delegate())+0x2a) [0x43abba]
./q(extern (C) int rt.dmain2.main(int, char**).void runAll()+0x3b) [0x43b287]
./q(extern (C) int rt.dmain2.main(int, char**).void tryExec(scope void delegate())+0x2a) [0x43abba]
./q(main+0xd1) [0x43ab45]
/usr/lib/libc.so.6(__libc_start_main+0xf5) [0x7f1286cc0725]
----------------
Just parsing out bool when it's first and then parsing _nothing_ else works, but it seems like parsing it under any other circumstances fails (from what I can tell anyway).
Comment #1 by monarchdodra — 2012-09-26T13:48:08Z
(In reply to comment #0)
> This code
>
> import std.conv;
> import std.stdio;
>
> void main()
> {
> auto str = "123 456.7 false";
>
> auto i = parse!int(str);
> auto d = parse!double(str);
> auto b = parse!bool(str);
>
> assert(i == 123);
> assert(d == 456.7);
> assert(b == false);
> }
>
> results in this exception when you run it
>
> std.conv.ConvException@std/conv.d(2654): Can't parse string: bool should be
> case-insensive 'true' or 'false'
> ----------------
> ./q(bool std.conv.parse!(bool, immutable(char)[]).parse(ref
> immutable(char)[])+0x183) [0x43867b]
> ./q(_Dmain+0x42) [0x430ec2]
> ./q(extern (C) int rt.dmain2.main(int, char**).void runMain()+0x1c) [0x43b240]
> ./q(extern (C) int rt.dmain2.main(int, char**).void tryExec(scope void
> delegate())+0x2a) [0x43abba]
> ./q(extern (C) int rt.dmain2.main(int, char**).void runAll()+0x3b) [0x43b287]
> ./q(extern (C) int rt.dmain2.main(int, char**).void tryExec(scope void
> delegate())+0x2a) [0x43abba]
> ./q(main+0xd1) [0x43ab45]
> /usr/lib/libc.so.6(__libc_start_main+0xf5) [0x7fd238fc1725]
> ----------------
>
> If you change it to
>
> import std.conv;
> import std.stdio;
>
> void main()
> {
> auto str = "false 123 456.7";
>
> auto b = parse!bool(str);
> auto i = parse!int(str);
> auto d = parse!double(str);
>
> assert(i == 123);
> assert(d == 456.7);
> assert(b == false);
> }
>
> you get
>
> std.conv.ConvException@std/conv.d(1771): Unexpected ' ' when converting from
> type string to type int
> ----------------
> ./q(int std.conv.parse!(int, immutable(char)[]).parse(ref
> immutable(char)[])+0x1b8) [0x431984]
> ./q(_Dmain+0x33) [0x430eb3]
> ./q(extern (C) int rt.dmain2.main(int, char**).void runMain()+0x1c) [0x43b240]
> ./q(extern (C) int rt.dmain2.main(int, char**).void tryExec(scope void
> delegate())+0x2a) [0x43abba]
> ./q(extern (C) int rt.dmain2.main(int, char**).void runAll()+0x3b) [0x43b287]
> ./q(extern (C) int rt.dmain2.main(int, char**).void tryExec(scope void
> delegate())+0x2a) [0x43abba]
> ./q(main+0xd1) [0x43ab45]
> /usr/lib/libc.so.6(__libc_start_main+0xf5) [0x7f1286cc0725]
> ----------------
>
> Just parsing out bool when it's first and then parsing _nothing_ else works,
> but it seems like parsing it under any other circumstances fails (from what I
> can tell anyway).
Sounds like the implementation is looking for a literal "true" or "false", and is forgetting to skip leading ws.
This works:
import std.conv;
import std.stdio;
void main()
{
auto str = "123 456.7 false";
auto i = parse!int(str);
auto d = parse!double(str);
str = str[1..$]; //manually skip ws.
auto b = parse!bool(str);
assert(i == 123);
assert(d == 456.7);
assert(b == false);
}
I can look into it for next week, unless somebody else solves it by then.
Comment #2 by monarchdodra — 2012-09-26T13:52:15Z
(In reply to comment #1)
> (In reply to comment #0)
> > This code
> >
> > import std.conv;
> > import std.stdio;
> >
> > void main()
> > {
> > auto str = "123 456.7 false";
> >
> > auto i = parse!int(str);
> > auto d = parse!double(str);
> > auto b = parse!bool(str);
> >
> > assert(i == 123);
> > assert(d == 456.7);
> > assert(b == false);
> > }
> >
> > results in this exception when you run it
> >
> > std.conv.ConvException@std/conv.d(2654): Can't parse string: bool should be
> > case-insensive 'true' or 'false'
> > ----------------
> > ./q(bool std.conv.parse!(bool, immutable(char)[]).parse(ref
> > immutable(char)[])+0x183) [0x43867b]
> > ./q(_Dmain+0x42) [0x430ec2]
> > ./q(extern (C) int rt.dmain2.main(int, char**).void runMain()+0x1c) [0x43b240]
> > ./q(extern (C) int rt.dmain2.main(int, char**).void tryExec(scope void
> > delegate())+0x2a) [0x43abba]
> > ./q(extern (C) int rt.dmain2.main(int, char**).void runAll()+0x3b) [0x43b287]
> > ./q(extern (C) int rt.dmain2.main(int, char**).void tryExec(scope void
> > delegate())+0x2a) [0x43abba]
> > ./q(main+0xd1) [0x43ab45]
> > /usr/lib/libc.so.6(__libc_start_main+0xf5) [0x7fd238fc1725]
> > ----------------
> >
> > If you change it to
> >
> > import std.conv;
> > import std.stdio;
> >
> > void main()
> > {
> > auto str = "false 123 456.7";
> >
> > auto b = parse!bool(str);
> > auto i = parse!int(str);
> > auto d = parse!double(str);
> >
> > assert(i == 123);
> > assert(d == 456.7);
> > assert(b == false);
> > }
> >
> > you get
> >
> > std.conv.ConvException@std/conv.d(1771): Unexpected ' ' when converting from
> > type string to type int
> > ----------------
> > ./q(int std.conv.parse!(int, immutable(char)[]).parse(ref
> > immutable(char)[])+0x1b8) [0x431984]
> > ./q(_Dmain+0x33) [0x430eb3]
> > ./q(extern (C) int rt.dmain2.main(int, char**).void runMain()+0x1c) [0x43b240]
> > ./q(extern (C) int rt.dmain2.main(int, char**).void tryExec(scope void
> > delegate())+0x2a) [0x43abba]
> > ./q(extern (C) int rt.dmain2.main(int, char**).void runAll()+0x3b) [0x43b287]
> > ./q(extern (C) int rt.dmain2.main(int, char**).void tryExec(scope void
> > delegate())+0x2a) [0x43abba]
> > ./q(main+0xd1) [0x43ab45]
> > /usr/lib/libc.so.6(__libc_start_main+0xf5) [0x7f1286cc0725]
> > ----------------
> >
> > Just parsing out bool when it's first and then parsing _nothing_ else works,
> > but it seems like parsing it under any other circumstances fails (from what I
> > can tell anyway).
>
> Sounds like the implementation is looking for a literal "true" or "false", and
> is forgetting to skip leading ws.
>
> [SNIP]
Bigtime!
// string to bool conversions
Target parse(Target, Source)(ref Source s)
if (isSomeString!Source && !is(Source == enum) &&
is(Unqual!Target == bool))
{
if (s.length >= 4 && icmp(s[0 .. 4], "true")==0)
{
s = s[4 .. $];
return true;
}
if (s.length >= 5 && icmp(s[0 .. 5], "false")==0)
{
s = s[5 .. $];
return false;
}
parseError("bool should be case-insensive 'true' or 'false'");
assert(0);
}
I got this.
Comment #3 by monarchdodra — 2012-09-26T14:36:53Z
FYI, parse!int also has the same problem. Only floating point types seem to behave correctly:
import std.conv;
import std.stdio;
void main()
{
auto str = "456.7 123";
auto d = parse!double(str);
auto i = parse!int(str);
assert(d == 456.7);
assert(i == 123);
}
On the split side, to! seems to parse things it should actually be rejecting:
import std.conv;
import std.stdio;
void main()
{
auto str = "456.7 123";
auto d = to!double(" 456.7"); //Passes, but shouldn't
auto i = to!int(" 123"); //Correctly throws
}
Just logging here the bugs I find, still on this.
Comment #4 by monarchdodra — 2012-09-27T13:40:52Z
(In reply to comment #0)
> This code
>
> import std.conv;
> import std.stdio;
>
> void main()
> {
> auto str = "123 456.7 false";
>
> auto i = parse!int(str);
> auto d = parse!double(str);
> auto b = parse!bool(str);
>
> assert(i == 123);
> assert(d == 456.7);
> assert(b == false);
> }
>
> results in this exception when you run it
>
> std.conv.ConvException@std/conv.d(2654): Can't parse string: bool should be
> case-insensive 'true' or 'false'
> ----------------
> ./q(bool std.conv.parse!(bool, immutable(char)[]).parse(ref
> immutable(char)[])+0x183) [0x43867b]
> ./q(_Dmain+0x42) [0x430ec2]
> ./q(extern (C) int rt.dmain2.main(int, char**).void runMain()+0x1c) [0x43b240]
> ./q(extern (C) int rt.dmain2.main(int, char**).void tryExec(scope void
> delegate())+0x2a) [0x43abba]
> ./q(extern (C) int rt.dmain2.main(int, char**).void runAll()+0x3b) [0x43b287]
> ./q(extern (C) int rt.dmain2.main(int, char**).void tryExec(scope void
> delegate())+0x2a) [0x43abba]
> ./q(main+0xd1) [0x43ab45]
> /usr/lib/libc.so.6(__libc_start_main+0xf5) [0x7fd238fc1725]
> ----------------
>
> If you change it to
>
> import std.conv;
> import std.stdio;
>
> void main()
> {
> auto str = "false 123 456.7";
>
> auto b = parse!bool(str);
> auto i = parse!int(str);
> auto d = parse!double(str);
>
> assert(i == 123);
> assert(d == 456.7);
> assert(b == false);
> }
>
> you get
>
> std.conv.ConvException@std/conv.d(1771): Unexpected ' ' when converting from
> type string to type int
> ----------------
> ./q(int std.conv.parse!(int, immutable(char)[]).parse(ref
> immutable(char)[])+0x1b8) [0x431984]
> ./q(_Dmain+0x33) [0x430eb3]
> ./q(extern (C) int rt.dmain2.main(int, char**).void runMain()+0x1c) [0x43b240]
> ./q(extern (C) int rt.dmain2.main(int, char**).void tryExec(scope void
> delegate())+0x2a) [0x43abba]
> ./q(extern (C) int rt.dmain2.main(int, char**).void runAll()+0x3b) [0x43b287]
> ./q(extern (C) int rt.dmain2.main(int, char**).void tryExec(scope void
> delegate())+0x2a) [0x43abba]
> ./q(main+0xd1) [0x43ab45]
> /usr/lib/libc.so.6(__libc_start_main+0xf5) [0x7f1286cc0725]
> ----------------
>
> Just parsing out bool when it's first and then parsing _nothing_ else works,
> but it seems like parsing it under any other circumstances fails (from what I
> can tell anyway).
https://github.com/D-Programming-Language/phobos/pull/817
Comment #5 by k.hara.pg — 2012-09-27T18:29:09Z
(In reply to comment #3)
> FYI, parse!int also has the same problem. Only floating point types seem to
> behave correctly:
NO, this is just a bug in `T parse!T(input) if (isFloatingPoint!T)`.
The parse function family should not skip leading white spaces implicitly.
I think it is simple, no special cases, and flexible design.
See also my github comment to the pull#817:
https://github.com/D-Programming-Language/phobos/pull/817#issuecomment-8960280
Comment #6 by github-bugzilla — 2012-10-04T09:33:06Z