How to correctly write regular expression to match ASCII control chars
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
asked Apr 14 at 14:54
sergheiserghei
189110
add a comment |
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
asked Apr 14 at 14:54
sergheiserghei
189110
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
Apr 14 at 15:34
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
Apr 14 at 16:13
And as I can seeÀis defined in ASCII: ascii-code.com. 0xC0 is between 0x7F and 0xFF
– serghei
Apr 14 at 16:19
add a comment |
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
asked Apr 14 at 14:54
sergheiserghei
189110
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
asked Apr 14 at 14:54
sergheiserghei
189110
asked Apr 14 at 14:54
sergheiserghei
189110
edited Apr 14 at 15:59
serghei
asked Apr 14 at 14:54
sergheiserghei
189110
asked Apr 14 at 14:54
sergheiserghei
189110
asked Apr 14 at 14:54
sergheiserghei
189110
189110
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
Apr 14 at 15:34
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
Apr 14 at 16:13
And as I can seeÀis defined in ASCII: ascii-code.com. 0xC0 is between 0x7F and 0xFF
– serghei
Apr 14 at 16:19
add a comment |
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
Apr 14 at 15:34
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
Apr 14 at 16:13
And as I can seeÀis defined in ASCII: ascii-code.com. 0xC0 is between 0x7F and 0xFF
– serghei
Apr 14 at 16:19
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
Apr 14 at 15:34
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
Apr 14 at 15:34
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
Apr 14 at 16:13
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
Apr 14 at 16:13
And as I can see
À is defined in ASCII: ascii-code.com. 0xC0 is between 0x7F and 0xFF– serghei
Apr 14 at 16:19
And as I can see
À is defined in ASCII: ascii-code.com. 0xC0 is between 0x7F and 0xFF– serghei
Apr 14 at 16:19
add a comment |
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 ]
answered Apr 14 at 17:46
DrewDrew
49.3k463108
add a comment |
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1 Answer
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votes
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 ]
answered Apr 14 at 17:46
DrewDrew
49.3k463108
add a comment |
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 ]
answered Apr 14 at 17:46
DrewDrew
49.3k463108
add a comment |
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 ]
answered Apr 14 at 17:46
DrewDrew
49.3k463108
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 ]
answered Apr 14 at 17:46
DrewDrew
49.3k463108
edited Apr 14 at 17:52
answered Apr 14 at 17:46
DrewDrew
49.3k463108
answered Apr 14 at 17:46
DrewDrew
49.3k463108
answered Apr 14 at 17:46
DrewDrew
49.3k463108
49.3k463108
add a comment |
add a comment |
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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
Apr 14 at 15:34
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
Apr 14 at 16:13
And as I can see
Àis defined in ASCII: ascii-code.com. 0xC0 is between 0x7F and 0xFF– serghei
Apr 14 at 16:19