Re: Fwd: Re: Re: bug in field-string and field-string-no-properties

[Greg Hill <ghill@synergymicro.com>]

At 5:32 PM -0400 8/28/03, Stefan Monnier wrote:
<snip>
>
>  > As it stands, field-string returns a string only if the character to
>  > the left AND the character to the right of POS both have the same
>  > field property.
>
>Can you show a precise test case that shows that ?
>It works correctly in my tests (and in actual use by `customize' it also
>seems to work).

(progn
   (set-buffer (get-buffer-create "junk"))
   (erase-buffer)
   (insert "xXyY")
   (put-text-property 1 3 'field 'X)
   (put-text-property 3 5 'field 'Y)
   (message (concat "At 1, field-property = %s, field-string = '%s'\n"
		   " At 2, field-property = %s, field-string = '%s'\n"
		   " At 3, field-property = %s, field-string = '%s'\n"
		   " At 4, field-property = %s, field-string = '%s'\n"
		   " At 5, field-property = %s, field-string = '%s'\n")
	   (get-text-property 1 'field) (field-string-no-properties 1)
	   (get-text-property 2 'field) (field-string-no-properties 2)
	   (get-text-property 3 'field) (field-string-no-properties 3)
	   (get-text-property 4 'field) (field-string-no-properties 4)
	   (get-text-property 5 'field) (field-string-no-properties 5)))

produces:

"At 1, field-property = X, field-string = ''
  At 2, field-property = X, field-string = 'xX'
  At 3, field-property = Y, field-string = ''
  At 4, field-property = Y, field-string = 'yY'
  At 5, field-property = nil, field-string = ''
"

The kind of function I would find useful wouldn't depend on 
stickiness at all.  For a given buffer position, the value of the 
field property returned by get-text-property would determine the 
string returned by field-string when it is passed the same buffer 
position.  Thus, in the example above, since the characters at 
positions 3 and 4 both have the same value, 'Y, for their field 
property, field-string would return the same string, "yY", for both 
of those positions.  If this were the case, the `buffer-pos' in the 
event caused by mouse-clicking on the "y" at position 3 in the 
example above would always return "yY" as the field-string, not an 
empty string, and certainly not "xX" just because the "X" happened to 
be rear-sticky.

--Greg