[XML-DEV Mailing List Archive Home] [By Thread] [By Date] [Recent Entries] [Reply To This Message]

Re: XML: why there is no escape (was Re: Whatto esca

• From: Rick Marshall <rjm@z...>
• To: Michael Kay <mike@s...>
• Date: Thu, 04 Jan 2007 09:35:31 +1100

I could be confused too, but it seems to me that "\" in C like languages 
and shell scripts etc is equivalent to "&" in XML.

In both cases there is only one really special character that can be 
used to change the meaning of the following character(s).

I don't know why, but I'm guessing Dennis Ritchie chose the "\" instead 
of ESC because it was infrequently used (Unix uses "/" as a directory 
separator - no idea why MS decided later to confuse the issue with "\") 
and it's printable on a KSR 33 (which an ESC is not) and the old 
DECWRITER (option B as a terminal device).

Personally I think it would have been better for XML (SGML?) to stick to 
an existing programming practice (and {} instead of <>) - but the 
document world had evolving differently to the programming world and I 
guess we just have to live with clash of cultures.

Rick

Michael Kay wrote:
>> To escape a character means to do something (typically, to 
>> prefix it with \ in C-family languages) to allow the 
>> character to be used literally but without its normal parser 
>> treatment.  So \ before a newline in a shell script is an 
>> escaped character. 
>>     
>
> Kernighan and Ritchie don't use "escape" as a verb, but they do refer to
> constructs such as "\n" and "\b" as "escape sequences". So it seems fairly
> natural that people should use the verb "escape [a character]" to mean
> "represent [a character] by means of an escape sequence". Representing tab
> by "\t" doesn't seem very different from representing tab by "&#x9;", so
> it's natural that the same verb should be used for that too.
>
> Michael Kay
> http://www.saxonica.com/
>
>
> _______________________________________________________________________
>
> XML-DEV is a publicly archived, unmoderated list hosted by OASIS
> to support XML implementation and development. To minimize
> spam in the archives, you must subscribe before posting.
>
> [Un]Subscribe/change address: http://www.oasis-open.org/mlmanage/
> Or unsubscribe: xml-dev-unsubscribe@l...
> subscribe: xml-dev-subscribe@l...
> List archive: http://lists.xml.org/archives/xml-dev/
> List Guidelines: http://www.oasis-open.org/maillists/guidelines.php
>
>   

• Follow-Ups:
  • Re: XML: why there is no escape (was Re: Whatto escape when serializing XML)
    • From: Rick Jelliffe <rjelliffe@a...>

• References:
  • RE: XML: why there is no escape (was Re: What to escape when serializing XML)
    • From: "Michael Kay" <mike@s...>