How to correctly write regular expression to match ASCII control chars












2















I would like to to create a regular expression in elisp (in the standard 'read' form) to match extended ASCII chars the same as PCRE does:



^[a-zA-Z_x7f-xff][a-zA-Z0-9_x7f-xff]*$


So, I'm currently сonfused about x7f-xff. Is there a way to set a range using something like xhh?






regular-expressions







share|improve this question

























  • I think the answer depends on whether you're matching against unibyte or multibyte strings. Do you think À (which is undefined in ASCII, 0xC0 in latin-1 and Unicode, but encoded as 0xC380 in UTF-8) falls into the range 0x7F-0xFF?

    – npostavs
    5 hours ago











  • I think so. At least PCRE matched À as a char in 0x7F-0xFF range. I need the same behavior for standard Elisp regular expression.

    – serghei
    5 hours ago













  • And as I can see À is defined in ASCII: ascii-code.com. 0xC0 is between 0x7F and 0xFF

    – serghei
    4 hours ago
















2















I would like to to create a regular expression in elisp (in the standard 'read' form) to match extended ASCII chars the same as PCRE does:



^[a-zA-Z_x7f-xff][a-zA-Z0-9_x7f-xff]*$


So, I'm currently сonfused about x7f-xff. Is there a way to set a range using something like xhh?






regular-expressions







share|improve this question

























  • I think the answer depends on whether you're matching against unibyte or multibyte strings. Do you think À (which is undefined in ASCII, 0xC0 in latin-1 and Unicode, but encoded as 0xC380 in UTF-8) falls into the range 0x7F-0xFF?

    – npostavs
    5 hours ago











  • I think so. At least PCRE matched À as a char in 0x7F-0xFF range. I need the same behavior for standard Elisp regular expression.

    – serghei
    5 hours ago













  • And as I can see À is defined in ASCII: ascii-code.com. 0xC0 is between 0x7F and 0xFF

    – serghei
    4 hours ago














2












2








2


1






I would like to to create a regular expression in elisp (in the standard 'read' form) to match extended ASCII chars the same as PCRE does:



^[a-zA-Z_x7f-xff][a-zA-Z0-9_x7f-xff]*$


So, I'm currently сonfused about x7f-xff. Is there a way to set a range using something like xhh?






regular-expressions







share|improve this question
















I would like to to create a regular expression in elisp (in the standard 'read' form) to match extended ASCII chars the same as PCRE does:



^[a-zA-Z_x7f-xff][a-zA-Z0-9_x7f-xff]*$


So, I'm currently сonfused about x7f-xff. Is there a way to set a range using something like xhh?






regular-expressions




regular-expressions






share|improve this question















share|improve this question













share|improve this question




share|improve this question








edited 5 hours ago







serghei

















asked 6 hours ago









sergheiserghei

187110




187110













  • I think the answer depends on whether you're matching against unibyte or multibyte strings. Do you think À (which is undefined in ASCII, 0xC0 in latin-1 and Unicode, but encoded as 0xC380 in UTF-8) falls into the range 0x7F-0xFF?

    – npostavs
    5 hours ago











  • I think so. At least PCRE matched À as a char in 0x7F-0xFF range. I need the same behavior for standard Elisp regular expression.

    – serghei
    5 hours ago













  • And as I can see À is defined in ASCII: ascii-code.com. 0xC0 is between 0x7F and 0xFF

    – serghei
    4 hours ago



















  • I think the answer depends on whether you're matching against unibyte or multibyte strings. Do you think À (which is undefined in ASCII, 0xC0 in latin-1 and Unicode, but encoded as 0xC380 in UTF-8) falls into the range 0x7F-0xFF?

    – npostavs
    5 hours ago











  • I think so. At least PCRE matched À as a char in 0x7F-0xFF range. I need the same behavior for standard Elisp regular expression.

    – serghei
    5 hours ago













  • And as I can see À is defined in ASCII: ascii-code.com. 0xC0 is between 0x7F and 0xFF

    – serghei
    4 hours ago

















I think the answer depends on whether you're matching against unibyte or multibyte strings. Do you think À (which is undefined in ASCII, 0xC0 in latin-1 and Unicode, but encoded as 0xC380 in UTF-8) falls into the range 0x7F-0xFF?

– npostavs
5 hours ago





I think the answer depends on whether you're matching against unibyte or multibyte strings. Do you think À (which is undefined in ASCII, 0xC0 in latin-1 and Unicode, but encoded as 0xC380 in UTF-8) falls into the range 0x7F-0xFF?

– npostavs
5 hours ago













I think so. At least PCRE matched À as a char in 0x7F-0xFF range. I need the same behavior for standard Elisp regular expression.

– serghei
5 hours ago







I think so. At least PCRE matched À as a char in 0x7F-0xFF range. I need the same behavior for standard Elisp regular expression.

– serghei
5 hours ago















And as I can see À is defined in ASCII: ascii-code.com. 0xC0 is between 0x7F and 0xFF

– serghei
4 hours ago





And as I can see À is defined in ASCII: ascii-code.com. 0xC0 is between 0x7F and 0xFF

– serghei
4 hours ago










1 Answer
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You can use -ÿ instead of x7f-xff. That first character, which StackExchange prints as a space, is DEL, which has codepoint 127 (decimal), #o177 (octal), and #x7f (hexadecimal).



That is, you can just insert the characters themselves in the regexp pattern.



One way to input such characters is to use C-x 8 RET. To search for any char in the range x7f through xff you would type this at the C-M-s prompt (without the spaces):



[ C-x 8 RET # x 7 f - C-x 8 RET # x f f ]






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    1 Answer
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    active

    oldest

    votes








    1 Answer
    1






    active

    oldest

    votes









    active

    oldest

    votes






    active

    oldest

    votes









    0














    You can use -ÿ instead of x7f-xff. That first character, which StackExchange prints as a space, is DEL, which has codepoint 127 (decimal), #o177 (octal), and #x7f (hexadecimal).



    That is, you can just insert the characters themselves in the regexp pattern.



    One way to input such characters is to use C-x 8 RET. To search for any char in the range x7f through xff you would type this at the C-M-s prompt (without the spaces):



    [ C-x 8 RET # x 7 f - C-x 8 RET # x f f ]






    share|improve this answer






























      0














      You can use -ÿ instead of x7f-xff. That first character, which StackExchange prints as a space, is DEL, which has codepoint 127 (decimal), #o177 (octal), and #x7f (hexadecimal).



      That is, you can just insert the characters themselves in the regexp pattern.



      One way to input such characters is to use C-x 8 RET. To search for any char in the range x7f through xff you would type this at the C-M-s prompt (without the spaces):



      [ C-x 8 RET # x 7 f - C-x 8 RET # x f f ]






      share|improve this answer




























        0












        0








        0







        You can use -ÿ instead of x7f-xff. That first character, which StackExchange prints as a space, is DEL, which has codepoint 127 (decimal), #o177 (octal), and #x7f (hexadecimal).



        That is, you can just insert the characters themselves in the regexp pattern.



        One way to input such characters is to use C-x 8 RET. To search for any char in the range x7f through xff you would type this at the C-M-s prompt (without the spaces):



        [ C-x 8 RET # x 7 f - C-x 8 RET # x f f ]






        share|improve this answer















        You can use -ÿ instead of x7f-xff. That first character, which StackExchange prints as a space, is DEL, which has codepoint 127 (decimal), #o177 (octal), and #x7f (hexadecimal).



        That is, you can just insert the characters themselves in the regexp pattern.



        One way to input such characters is to use C-x 8 RET. To search for any char in the range x7f through xff you would type this at the C-M-s prompt (without the spaces):



        [ C-x 8 RET # x 7 f - C-x 8 RET # x f f ]







        share|improve this answer














        share|improve this answer



        share|improve this answer








        edited 3 hours ago

























        answered 3 hours ago









        DrewDrew

        49.1k463108




        49.1k463108






























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