Checking, whether string contains only ascii.

[jklm via Digitalmars-d-learn]

On Wednesday, 22 February 2017 at 19:57:22 UTC, jklm wrote:
> On Wednesday, 22 February 2017 at 19:26:15 UTC, berni wrote:
>> In my program, I read a postscript file. Normal postscript 
>> files should only be composed of ascii characters, but one 
>> never knows what users give us. Therefore I'd like to make 
>> sure that the string the program read is only made up of ascii 
>> characters. This simplifies the code thereafter, because I 
>> then can assume, that codeunit==codepoint. Is there a simple 
>> way to do so?
>>
>> Here a sketch of my function:
>>
>>>void foo(string postscript)
>>>{
>>>    // throw Exception, if postscript is not all ascii
>>>    // other stuff, assuming codeunit=codepoint
>>>}
>
>
> void foo(string postscript)
> {
>     import std.ascii, astd.algorithm.ieration;
>     if (!postscript.filter!(a => !isASCII(a)).empty)
>         throw new Exception("bla");
> }

\s  postscript args[0]