dc: Miscellaneous
1
1 10 Miscellaneous
1 ****************
1
1 '!'
1 Will run the rest of the line as a system command. Note that
1 parsing of the !<, !=, and !> commands take precedence, so if you
1 want to run a command starting with <, =, or > you will need to add
1 a space after the !.
1
1 '#'
1 Will interpret the rest of the line as a comment. (This command is
1 a GNU extension.)
1
1 ':R'
1 Will pop the top two values off of the stack. The old
1 second-to-top value will be stored in the array R, indexed by the
1 old top-of-stack value.
1
1 ';R'
1 Pops the top-of-stack and uses it as an index into the array R.
1 The selected value is then pushed onto the stack.
1
1 Note that each stacked instance of a register has its own array
1 associated with it. Thus '1 0:A 0SA 2 0:A LA 0;Ap' will print 1,
1 because the 2 was stored in an instance of 0:A that was later popped.
1