32.19 Text Properties

Each character position in a buffer or a string can have a text property list, much like the property list of a symbol (see section 8.4 Property Lists). The properties belong to a particular character at a particular place, such as, the letter `T' at the beginning of this sentence or the first `o' in `foo'---if the same character occurs in two different places, the two occurrences generally have different properties.

Each property has a name and a value. Both of these can be any Lisp object, but the name is normally a symbol. The usual way to access the property list is to specify a name and ask what value corresponds to it.

If a character has a category property, we call it the category of the character. It should be a symbol. The properties of the symbol serve as defaults for the properties of the character.

Copying text between strings and buffers preserves the properties along with the characters; this includes such diverse functions as substring, insert, and buffer-substring.

32.19.1 Examining Text Properties		Looking at the properties of one character.
32.19.2 Changing Text Properties		Setting the properties of a range of text.
32.19.3 Text Property Search Functions		Searching for where a property changes value.
32.19.4 Properties with Special Meanings		Particular properties with special meanings.
32.19.5 Formatted Text Properties		Properties for representing formatting of text.
32.19.6 Stickiness of Text Properties		How inserted text gets properties from neighboring text.
32.19.7 Saving Text Properties in Files		Saving text properties in files, and reading them back.
32.19.8 Lazy Computation of Text Properties		Computing text properties in a lazy fashion only when text is examined.
32.19.9 Defining Clickable Text		Using text properties to make regions of text do something when you click on them.
32.19.10 Defining and Using Fields		The field property defines fields within the buffer.
32.19.11 Why Text Properties are not Intervals		Why text properties do not use Lisp-visible text intervals.