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Converting an Array of Characters to a String

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kilon.alios

Nov 08, 2016; 1:22pm

Converting an Array of Characters to a String

2862 posts

I feel like stupid but I cannot find a way to convert an Array of Characters to a String , I can do with a do: and join characters converted to strings to a single string but it feels too many steps.

Is there a simpler way ?

Nicolai Hess-3-2

Nov 08, 2016; 1:32pm

Re: Converting an Array of Characters to a String

935 posts

2016-11-08 14:31 GMT+01:00 Dimitris Chloupis <[hidden email]>:

I feel like stupid but I cannot find a way to convert an Array of Characters to a String , I can do with a do: and join characters converted to strings to a single string but it feels too many steps.

Is there a simpler way ?

String newFrom:{ $a . $b . $c }.
{ $a . $b . $c } as:String.

EstebanLM

Nov 08, 2016; 1:33pm

Re: Converting an Array of Characters to a String

6187 posts

In reply to this post by kilon.alios

(always with Char100 example in mind):

s := MyStructure fromHandle: blah.
string := s data readString.

should work.

Esteban

> On 8 Nov 2016, at 14:31, Dimitris Chloupis <[hidden email]> wrote:
>
> I feel like stupid but I cannot find a way to convert an Array of Characters to a String , I can do with a do: and join characters converted to strings to a single string but it feels too many steps.
>
> Is there a simpler way ?

EstebanLM

Nov 08, 2016; 1:35pm

Re: Converting an Array of Characters to a String

6187 posts

In reply to this post by Nicolai Hess-3-2

ah yes, that will work (I was thinking on UFFI and I answered that) :)

On 8 Nov 2016, at 14:41, Nicolai Hess <[hidden email]> wrote:

2016-11-08 14:31 GMT+01:00 Dimitris Chloupis <[hidden email]>:
I feel like stupid but I cannot find a way to convert an Array of Characters to a String , I can do with a do: and join characters converted to strings to a single string but it feels too many steps.

Is there a simpler way ?

String newFrom:{ $a . $b . $c }.
{ $a . $b . $c } as:String.

kilon.alios

Nov 08, 2016; 1:43pm

Re: Converting an Array of Characters to a String

2862 posts

In reply to this post by Nicolai Hess-3-2

On Tue, Nov 8, 2016 at 3:42 PM Nicolai Hess <[hidden email]> wrote:

2016-11-08 14:31 GMT+01:00 Dimitris Chloupis <[hidden email]>:
I feel like stupid but I cannot find a way to convert an Array of Characters to a String , I can do with a do: and join characters converted to strings to a single string but it feels too many steps.

Is there a simpler way ?

String newFrom:{ $a . $b . $c }.
{ $a . $b . $c } as:String.

Its so weird that

{ $a . $b . $c } as:String.

works but

{ $a . $b . $c } asString.

does not

the latter returns a string that contains something like

{$S. $e. $d. Character space. $o. $r. $n. $a. $r. $e. C

In any case Thanks Nicolai it works :)

vonbecmann

Nov 08, 2016; 3:06pm

Re: Converting an Array of Characters to a String

296 posts

something similar

String withAll: { $a. Character space. $b }.

On Tue, Nov 8, 2016 at 10:52 AM, Dimitris Chloupis <[hidden email]> wrote:

On Tue, Nov 8, 2016 at 3:42 PM Nicolai Hess <[hidden email]> wrote:
2016-11-08 14:31 GMT+01:00 Dimitris Chloupis <[hidden email]>:
I feel like stupid but I cannot find a way to convert an Array of Characters to a String , I can do with a do: and join characters converted to strings to a single string but it feels too many steps.

Is there a simpler way ?

String newFrom:{ $a . $b . $c }.
{ $a . $b . $c } as:String.

Its so weird that

{ $a . $b . $c } as:String.

works but

{ $a . $b . $c } asString.

does not

the latter returns a string that contains something like

{$S. $e. $d. Character space. $o. $r. $n. $a. $r. $e. C

In any case Thanks Nicolai it works :)

... [show rest of quote]

Bernardo E.C.

Sent from a cheap desktop computer in South America.

Igor Stasenko

Nov 09, 2016; 1:29am

Re: Converting an Array of Characters to a String

9533 posts

In reply to this post by EstebanLM

On 8 November 2016 at 14:42, Esteban Lorenzano <[hidden email]> wrote:

(always with Char100 example in mind):

s := MyStructure fromHandle: blah.
string := s data readString.

should work.

IIRC, #readString works correctly only for correctly null-terminated strings. If not, it will read beyond the structure size , until it find a zero byte somewhere in memory,
and thus, results may vary :)

Esteban

> On 8 Nov 2016, at 14:31, Dimitris Chloupis <[hidden email]> wrote:
>
> I feel like stupid but I cannot find a way to convert an Array of Characters to a String , I can do with a do: and join characters converted to strings to a single string but it feels too many steps.
>
> Is there a simpler way ?

Best regards,
Igor Stasenko.

Igor Stasenko

Nov 09, 2016; 1:31am

Re: Converting an Array of Characters to a String

9533 posts

What i meant, i wanted to warn Dimitris that
char[100]
are just array of 100 characters (bytes in C).. and has nothing to do with strings.
Do not confuse fixed-length C arrays with strings. There's no 'string' data type in C, and instead they use null-terminated character sequence as a convention. But it is not a fixed-size data.

On 9 November 2016 at 02:38, Igor Stasenko <[hidden email]> wrote:

On 8 November 2016 at 14:42, Esteban Lorenzano <[hidden email]> wrote:
(always with Char100 example in mind):

s := MyStructure fromHandle: blah.
string := s data readString.

should work.

IIRC, #readString works correctly only for correctly null-terminated strings. If not, it will read beyond the structure size , until it find a zero byte somewhere in memory,
and thus, results may vary :)

Esteban

> On 8 Nov 2016, at 14:31, Dimitris Chloupis <[hidden email]> wrote:
>
> I feel like stupid but I cannot find a way to convert an Array of Characters to a String , I can do with a do: and join characters converted to strings to a single string but it feels too many steps.
>
> Is there a simpler way ?

--
Best regards,
Igor Stasenko.

... [show rest of quote]

Best regards,
Igor Stasenko.

kilon.alios

Nov 09, 2016; 6:40am

Re: Converting an Array of Characters to a String

2862 posts

Not in C but there std::string in C++ similar to our String object.

C char indeed is more a byte array than a string. Actually C won't allow to change the string value mainly because it thinks you try to change the size which something that is not allowed for arrays anyway, so the only way to change a char string aka char array is character by character. 

Null termination is why I filled the shared memory with zeros to be on the safe side and then added the string and the number on top

On Wed, 9 Nov 2016 at 03:41, Igor Stasenko <[hidden email]> wrote:

What i meant, i wanted to warn Dimitris that
char[100]
are just array of 100 characters (bytes in C).. and has nothing to do with strings.
Do not confuse fixed-length C arrays with strings. There's no 'string' data type in C, and instead they use null-terminated character sequence as a convention. But it is not a fixed-size data.

On 9 November 2016 at 02:38, Igor Stasenko <[hidden email]> wrote:

On 8 November 2016 at 14:42, Esteban Lorenzano <[hidden email]> wrote:
(always with Char100 example in mind):

s := MyStructure fromHandle: blah.
string := s data readString.

should work.

IIRC, #readString works correctly only for correctly null-terminated strings. If not, it will read beyond the structure size , until it find a zero byte somewhere in memory,
and thus, results may vary :)

Esteban

> On 8 Nov 2016, at 14:31, Dimitris Chloupis <[hidden email]> wrote:
>
> I feel like stupid but I cannot find a way to convert an Array of Characters to a String , I can do with a do: and join characters converted to strings to a single string but it feels too many steps.
>
> Is there a simpler way ?

--
Best regards,
Igor Stasenko.

... [show rest of quote]

--
Best regards,
Igor Stasenko.

... [show rest of quote]

Igor Stasenko

Nov 10, 2016; 2:25am

Re: Converting an Array of Characters to a String

9533 posts

On 9 November 2016 at 07:49, Dimitris Chloupis <[hidden email]> wrote:

Not in C but there std::string in C++ similar to our String object.

Strictly speaking , std::string is again not part of C++ per se, it comes from library that implements such class.

C char indeed is more a byte array than a string. Actually C won't allow to change the string value mainly because it thinks you try to change the size which something that is not allowed for arrays anyway, so the only way to change a char string aka char array is character by character.

Null termination is why I filled the shared memory with zeros to be on the safe side and then added the string and the number on top

just wanted to warn you, to make sure you understand that char[100] is not string, not in C , not in C++. And, of course, it should not autoconvert to smalltalk String object(s) in FFI, because many C coders use 'char' as a default data type to operate with buffers of certain length and to count their size in bytes.

On Wed, 9 Nov 2016 at 03:41, Igor Stasenko <[hidden email]> wrote:
What i meant, i wanted to warn Dimitris that
char[100]
are just array of 100 characters (bytes in C).. and has nothing to do with strings.
Do not confuse fixed-length C arrays with strings. There's no 'string' data type in C, and instead they use null-terminated character sequence as a convention. But it is not a fixed-size data.

On 9 November 2016 at 02:38, Igor Stasenko <[hidden email]> wrote:

On 8 November 2016 at 14:42, Esteban Lorenzano <[hidden email]> wrote:
(always with Char100 example in mind):

s := MyStructure fromHandle: blah.
string := s data readString.

should work.

IIRC, #readString works correctly only for correctly null-terminated strings. If not, it will read beyond the structure size , until it find a zero byte somewhere in memory,
and thus, results may vary :)

Esteban

> On 8 Nov 2016, at 14:31, Dimitris Chloupis <[hidden email]> wrote:
>
> I feel like stupid but I cannot find a way to convert an Array of Characters to a String , I can do with a do: and join characters converted to strings to a single string but it feels too many steps.
>
> Is there a simpler way ?

--
Best regards,
Igor Stasenko.

... [show rest of quote]

--
Best regards,
Igor Stasenko.

... [show rest of quote]

... [show rest of quote]

Best regards,
Igor Stasenko.