www.digitalmars.com         C & C++   DMDScript  

digitalmars.D.learn - Data conversion

reply pascal111 <judas.the.messiah.111 gmail.com> writes:
I used "to" keyword which "std.conv" includes for data 
conversions, but I think that there are some other ways for data 
conversions, or maybe there are common ways like casting, I hope 
to know about. For example, next program are using "to":

// D programming language

import std.stdio;
import std.conv;
import std.string;

int main()
{

char[] s;
int x=0, e;


do{

try{
e=1;
write("Enter a numeric value: ");
readln(s);
s=strip(s);
x=to!int(s);}

catch (Exception err){
stderr.writefln!"Warning! %s"(err.msg);
e=0;}

}while(!e);

writeln("Correct numeric value!");

return 0;

}
Nov 16 2021
next sibling parent reply Ferhat =?UTF-8?B?S3VydHVsbXXFnw==?= <aferust gmail.com> writes:
On Tuesday, 16 November 2021 at 19:18:50 UTC, pascal111 wrote:

 I used "to" keyword which "std.conv" includes for data 
 conversions, but I think that there are some other ways for 
 data conversions, or maybe there are common ways like casting, 
 I hope to know about. For example, next program are using "to":

 // D programming language

 import std.stdio;
 import std.conv;
 import std.string;

 int main()
 {

 char[] s;
 int x=0, e;


 do{

 try{
 e=1;
 write("Enter a numeric value: ");
 readln(s);
 s=strip(s);
 x=to!int(s);}

 catch (Exception err){
 stderr.writefln!"Warning! %s"(err.msg);
 e=0;}

 }while(!e);

 writeln("Correct numeric value!");

 return 0;

 }


sscanf of C is an option where you cannot use to!T. However, it 
is a c library function, and it doesn't throw an exception on 
unexpected inputs.

https://dlang.org/library/core/stdc/stdio/scanf.html
https://www.tutorialspoint.com/c_standard_library/c_function_sscanf.htm
Nov 16 2021
parent Ferhat =?UTF-8?B?S3VydHVsbXXFnw==?= <aferust gmail.com> writes:
On Tuesday, 16 November 2021 at 19:44:04 UTC, Ferhat Kurtulmuş 
wrote:

 On Tuesday, 16 November 2021 at 19:18:50 UTC, pascal111 wrote:

 [...]


 sscanf of C is an option where you cannot use to!T. However, it 
 is a c library function, and it doesn't throw an exception on 
 unexpected inputs.

 https://dlang.org/library/core/stdc/stdio/scanf.html
 https://www.tutorialspoint.com/c_standard_library/c_function_sscanf.htm



Upps

https://dlang.org/library/core/stdc/stdio/sscanf.html
Nov 16 2021
prev sibling parent jfondren <julian.fondren gmail.com> writes:
On Tuesday, 16 November 2021 at 19:18:50 UTC, pascal111 wrote:

 I used "to" keyword which "std.conv" includes for data 
 conversions, but I think that there are some other ways for 
 data conversions, or maybe there are common ways like casting, 
 I hope to know about. For example, next program are using "to":


Strictly speaking it's not a keyword, just a template name.

std.conv is pretty good for conversions like this. You can read 
about casting at 
https://dlang.org/spec/expression.html#CastExpression , and I 
have a quickref for string conversions at 
https://d.minimaltype.com/index.cgi/wiki?name=string+type+conversions

There's a lot to say about string conversions. Phobos date&time 
conversions deserve a quickref like that, too. On numerical 
conversions, D is very similar to other languages. OOP casting is 
noteworthy in that it can fail with `null`.
Nov 16 2021