The most basic way to use the expression parser is to tell it to start at a given position with a certain state, and parse up to a specified end position.
parse-partial-sexpstart limit &optional target-depth stop-before state stop-comment
This function parses a sexp in the current buffer starting at start, not scanning past limit. It stops at position limit or when certain criteria described below are met, and sets point to the location where parsing stops. It returns a parser state describing the status of the parse at the point where it stops.
If the third argument target-depth is non-
stops if the depth in parentheses becomes equal to target-depth.
The depth starts at 0, or at whatever is given in state.
If the fourth argument stop-before is non-
stops when it comes to any character that starts a sexp. If
stop-comment is non-
nil, parsing stops when it comes to the
start of a comment. If stop-comment is the symbol
syntax-table, parsing stops after the start of a comment or a
string, or the end of a comment or a string, whichever comes first.
If state is
nil, start is assumed to be at the top
level of parenthesis structure, such as the beginning of a function
definition. Alternatively, you might wish to resume parsing in the
middle of the structure. To do this, you must provide a state
argument that describes the initial status of parsing. The value
returned by a previous call to
parse-partial-sexp will do