Hi,

I'm looking for a function that converts my hex-string to a binary representation. In Python I write the following:

myHex = "123456789ABCDEF"
myBin = myHex.decode('hex')

But how to do the same in D? Is there any function?

Thanks for suggestions!

On 04/24/2015 11:14 AM, nrgyzer wrote:
> Hi,
>
> I'm looking for a function that converts my hex-string to a binary
> representation. In Python I write the following:
>
> myHex = "123456789ABCDEF"
> myBin = myHex.decode('hex')
>
> But how to do the same in D? Is there any function?
>
> Thanks for suggestions!

Here is one way:

import std.stdio;
import std.format;

string hexToBin(string source)
{
    ulong value;
    formattedRead(source, "%x", &value);
    return format("%b", value);
}

enum string hex = "hex";

string decode(string TargetFormat)(string source)
{
    static if (TargetFormat == "hex") {
        return hexToBin(source);

    } else {
        static assert(false,
                      format("I don't know how to decode to '%s'",
                             TargetFormat));
        return "";
    }
}

void main()
{
    assert("123456789ABCDEF".decode!hex ==
           "100100011010001010110011110001001101010111100110111101111");
}

Ali

On 4/24/15 2:14 PM, nrgyzer wrote:
> Hi,
>
> I'm looking for a function that converts my hex-string to a binary
> representation. In Python I write the following:
>
> myHex = "123456789ABCDEF"
> myBin = myHex.decode('hex')
>
> But how to do the same in D? Is there any function?
>
> Thanks for suggestions!

import std.conv : parse;
import std.stdio;

void main()
{
    auto myHex = "123456789ABCDEF";
    auto myBin = parse!ulong(myHex, 16);
    writeln(myBin); // 81985529216486895
}

Note, python may make arbitrary long integers, but D you must specify the size for your integer to the parse function. In this case, you need ulong which is 64 bits.

-Steve

On Friday, 24 April 2015 at 18:14:07 UTC, nrgyzer wrote:
> Hi,
>
> I'm looking for a function that converts my hex-string to a binary representation. In Python I write the following:
>
> myHex = "123456789ABCDEF"
> myBin = myHex.decode('hex')
>
> But how to do the same in D? Is there any function?
>
> Thanks for suggestions!

    import std.stdio;
    void main(){
        import std.conv;
        import std.format;

        auto i = to!ulong("123456789ABCDEF", 16);

        writeln(format("%b", i));
    }

On Friday, 24 April 2015 at 18:45:55 UTC, Jesse Phillips wrote:
> On Friday, 24 April 2015 at 18:14:07 UTC, nrgyzer wrote:
>> Hi,
>>
>> I'm looking for a function that converts my hex-string to a binary representation. In Python I write the following:
>>
>> myHex = "123456789ABCDEF"
>> myBin = myHex.decode('hex')
>>
>> But how to do the same in D? Is there any function?
>>
>> Thanks for suggestions!
>
>     import std.stdio;
>     void main(){
>         import std.conv;
>         import std.format;
>
>         auto i = to!ulong("123456789ABCDEF", 16);
>
>         writeln(format("%b", i));
>     }

Thanks to all of you for the solutions, but what if the hex-string exceeds the limit of ulong, for instance "123456789ABCDEF0123456789ABCDEF1234". How to convert them to a ulong-array?

On 4/24/15 2:50 PM, nrgyzer wrote:
> On Friday, 24 April 2015 at 18:45:55 UTC, Jesse Phillips wrote:
>> On Friday, 24 April 2015 at 18:14:07 UTC, nrgyzer wrote:
>>> Hi,
>>>
>>> I'm looking for a function that converts my hex-string to a binary
>>> representation. In Python I write the following:
>>>
>>> myHex = "123456789ABCDEF"
>>> myBin = myHex.decode('hex')
>>>
>>> But how to do the same in D? Is there any function?
>>>
>>> Thanks for suggestions!
>>
>>     import std.stdio;
>>     void main(){
>>         import std.conv;
>>         import std.format;
>>
>>         auto i = to!ulong("123456789ABCDEF", 16);
>>
>>         writeln(format("%b", i));
>>     }
>
> Thanks to all of you for the solutions, but what if the hex-string
> exceeds the limit of ulong, for instance
> "123456789ABCDEF0123456789ABCDEF1234". How to convert them to a
> ulong-array?

Well, technically, a hex string can be split on 16-character boundaries, and then you could parse each one.

-Steve

On Friday, 24 April 2015 at 18:55:07 UTC, Steven Schveighoffer wrote:
>> Thanks to all of you for the solutions, but what if the hex-string
>> exceeds the limit of ulong, for instance
>> "123456789ABCDEF0123456789ABCDEF1234". How to convert them to a
>> ulong-array?
>
> Well, technically, a hex string can be split on 16-character boundaries, and then you could parse each one.
>
> -Steve

BigInt can be constructed from a decimal string:

-----
import std.bigint, std.conv, std.stdio, std.string;
void main(){readln.strip.to!BigInt.writeln;}
-----

The same could have been done in the library for function "to" accepting the second argument, like this:

-----
import std.bigint, std.conv, std.stdio, std.string;
void main(){readln.strip.to!BigInt(16).writeln;}
-----

It seems trivial technically, but I wonder if there's some library design drawback.  After all, to!BigInt from the default base 10 is the same O(n^2) as to!BigInt from a variable base, so it's not like the function is going to hide complexity more than it already does.

Ivan Kazmenko.

On Friday, 24 April 2015 at 18:55:07 UTC, Steven Schveighoffer wrote:
> On 4/24/15 2:50 PM, nrgyzer wrote:
>> On Friday, 24 April 2015 at 18:45:55 UTC, Jesse Phillips wrote:
>>> On Friday, 24 April 2015 at 18:14:07 UTC, nrgyzer wrote:
>>>> Hi,
>>>>
>>>> I'm looking for a function that converts my hex-string to a binary
>>>> representation. In Python I write the following:
>>>>
>>>> myHex = "123456789ABCDEF"
>>>> myBin = myHex.decode('hex')
>>>>
>>>> But how to do the same in D? Is there any function?
>>>>
>>>> Thanks for suggestions!
>>>
>>>    import std.stdio;
>>>    void main(){
>>>        import std.conv;
>>>        import std.format;
>>>
>>>        auto i = to!ulong("123456789ABCDEF", 16);
>>>
>>>        writeln(format("%b", i));
>>>    }
>>
>> Thanks to all of you for the solutions, but what if the hex-string
>> exceeds the limit of ulong, for instance
>> "123456789ABCDEF0123456789ABCDEF1234". How to convert them to a
>> ulong-array?
>
> Well, technically, a hex string can be split on 16-character boundaries, and then you could parse each one.
>
> -Steve

Or use BigInt:

http://dlang.org/phobos/std_bigint.html

On Friday, 24 April 2015 at 19:15:04 UTC, Ivan Kazmenko wrote:
> On Friday, 24 April 2015 at 18:55:07 UTC, Steven Schveighoffer wrote:
>>> Thanks to all of you for the solutions, but what if the hex-string
>>> exceeds the limit of ulong, for instance
>>> "123456789ABCDEF0123456789ABCDEF1234". How to convert them to a
>>> ulong-array?
>>
>> Well, technically, a hex string can be split on 16-character boundaries, and then you could parse each one.
>>
>> -Steve
>
> BigInt can be constructed from a decimal string:
>
> -----
> import std.bigint, std.conv, std.stdio, std.string;
> void main(){readln.strip.to!BigInt.writeln;}
> -----
>
> The same could have been done in the library for function "to" accepting the second argument, like this:
>
> -----
> import std.bigint, std.conv, std.stdio, std.string;
> void main(){readln.strip.to!BigInt(16).writeln;}
> -----
>
> It seems trivial technically, but I wonder if there's some library design drawback.  After all, to!BigInt from the default base 10 is the same O(n^2) as to!BigInt from a variable base, so it's not like the function is going to hide complexity more than it already does.
>
> Ivan Kazmenko.

ATM BigInt already supports hex strings; it looks for a 0x prefix. A radix parameter would be nice, but this works today ;)