Hi Tom,
here's a little cursor positioning dialect, I just now
wrote, this is a very simple example, but easier to understand.
REBOL [
Title: "Cursor positioning dialect"
author: "Ingo Hohmann"
email: [EMAIL PROTECTED]
usage: {
print cursor2 [ home "My header" pos 13x13 "this starts at 13x13" up 3 "Hey" ]
print cursor2 [ clear "+" (screen-size/y - 2) "-" "+" "."
pos 2x1 "|" (screen-size/y - 2) " " "|" "."
pos 3x1 "+" (screen-size/y - 2) "-" "+" ]
}
known-bugs: [
{positioning problem, can't go to first column in the next row, when at end of
row
(try to skip the "." in second example
}
]
]
cursor2: func [
[catch]
commands [block!]
/local screen-size string arg cnt cmd c
][
; get the size of the screen
screen-size: (
c: open/binary [scheme: 'console]
prin "^(1B)[7n"
arg: next next to-string copy c
close c
arg: parse/all arg ";R"
forall arg [change arg to-integer first arg]
arg: to-pair head arg
)
; some setup
string: copy ""
cmd: func [s][join "^(1B)[" s]
; compose, so that () get reduced
commands: compose bind commands 'screen-size
; parse the dialect
arg: parse commands [
any [
'direct set arg string! (append string arg) |
'home (append string cmd "H") |
'kill (append string cmd "K") |
'clear (append string cmd "J") |
'up set arg integer! (append string cmd [arg "A"]) |
'down set arg integer! (append string cmd [arg "B"]) |
'right set arg integer! (append string cmd [arg "C"]) |
'left set arg integer! (append string cmd [arg "D"]) |
'pos set arg pair! (append string cmd [arg/x ";" arg/y "H" ]) |
'del set arg integer! (append string cmd [arg "P"]) |
'space set arg integer! (append string cmd [arg "@"]) |
'move set arg pair! (append string cmd [arg/x ";" arg/y "H" ]) |
set cnt integer! set arg string! (append string head insert/dup copy "" arg
cnt) |
set arg string! (append string arg)
]
]
if not arg [throw make error! "Unable to parse block"]
;return string to be printed
string
]
Once upon a time [EMAIL PROTECTED] spoketh thus:
> Hi,
>
> The subject says it all. This is the most interesting feature of the
> language and seems to be virtually undocumented. That can't be right can
> it???
