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THING may be a well known form as word, paragraph, but also a char class as `alnum' or a new defined thing.
For example ‘ar-alnum-atpt’ will return all alpha-numerical chars below and around cursor as a string. ‘ar-bounds-of-alnum-atpt’ returns the borders of that string as a list and so on.
‘ar-delimited-atpt’ will fetch buffer content, if point is between or at delimiter chars. See customizable vars ‘th-beg-delimiter’, ‘th-end-delimiter’, ‘ar-delimiters-atpt’.
Presently for a given THING the following is implemented:
ar-THING-atpt ar-THING-bounds-atpt ar-THING-beginning-position-atpt ar-THING-end-position-atpt ar-THING-backward-atpt ar-THING-forward-atpt ar-THING-length-atpt ar-THING-copy-atpt ar-THING-kill-atpt ar-THING-backward-atpt
A THING defined by unary delimiters like doublequotes: cursor needs to be between or at the start.