Library
Module
Module type
Parameter
Class
Class type
The allowed indentations: Helper module for indentation sensitive parsing.
type violation = expectation
val group :
('a * expectation option) list ->
(expectation option * 'a list) list
group lst
Group the list of expectations.
Failed expectations with the same indentation expectation (or not indentation expectation) are grouped into one list. The sequence is not changed.
val expectation : t -> expectation option
expectation ind
The expected indentation or alignment. Returns None
if all positions are allowed.
val initial : t
Initially all indentations 0,1,... are allowed and no alignment is required.
val check_position : int -> t -> expectation option
check_position col ind
Return a violated expectation, if pos
is not an allowed indentation position. Otherwise return None
.
token pos ind
Accept a token at column pos
.
Preconditions: is_position_allowed pos ind
.
align ind
Set the alignment flag.
The next token sets the indentation set to {pos}
where pos
is the column of the token and clears the aligment flag.
left_align ind
Set the alignment flag and the indentation set to {pos}
where pos
is the lower bound of the current set of indentation positions.
end_align ind0 ind
End the aligned sequence i.e. handle the corner case that the aligned sequence is empty.
start_indent i ind
Start an indented grammar construct indented by at least i
relative to its parent.
If the aligmnent flag is set, indentation is ignored.
Precondition: 0 <= incr