10.0;bl (balance) *DM*, revision 1.0, 88/03/09
bl (balance) - balance delimiters
usage: [range] bl [-i | -c] [l_char] [r_char]
DESCRIPTION
bl determines whether a given pair of delimiting characters (for
instance, left and right parentheses) is balanced within a specified
range of text.
ARGUMENTS
range (optional)
Specify a range of text to be checked. This argument is
valid only when used with -c; the range for -i is the
current cursor position to the end (or beginning) of the
file. Define the range to be checked as described in help
DM range.
Default if omitted: check from cursor to end of line.
l_char (optional)
Specify the left delimiting character. If you specify r_char
but omit this argument, the left delimiting character
defaults to r_char. If you omit both arguments, the left
delimiting character defaults to left parenthesis.
r_char (optional)
Specify the right delimiting character. If you specify
l_char but omit this argument, the right delimiting
character defaults to l_char. If you omit both arguments,
the right delimiting character defaults to right
parenthesis.
OPTIONS
If you specify either of the following options, it must precede any
arguments you specify.
-i (default) Insert mode: search for balanced delimiters from the current
character to the beginning or end of the file. The behavior
of bl depends upon the character under the cursor when you
invoke bl.
If you position the cursor on a delimiter and bl finds a
balancing delimiter, it moves the cursor to the matched
character momentarily (to show you where the balance is
completed), then returns the cursor to the character
immediately following the initial cursor postion. The search
direction is forward if the character under the cursor is a
left delimiter; backward if the character is a right
delimiter.
If you position the cursor on a delimiter and bl finds no
balancing delimiter, it gives an error message and sounds
the alarm, then inserts a matching right delimiter at the
initial cursor position.
If you position the cursor on a character other than a
delimiter, bl searches backward for the first occurrence of
l_char, briefly shows you where it is, then inserts a
matching right delimiter at the initial cursor position.
-c Check mode: check only; do not insert balancing characters
or move the cursor. You can mark a range of text to be
checked if you specify this option; see the range argument
above. bl checks all pairs of specified delimiters within
the specified range and displays the results in the DM
message window.