I have a personal productivity problem as I have a bunch of programs all over the place on my Desktop or in my Program Files Menu. I tried many launchers freewares but none really satisfied me so I finally decided to use Rebol Shell as my launcher. It’s also a great example of a context when you need to use the Bind function in Rebol.

So let’s say I have a list of programs I want to launch by just typing a keyword in Rebol Shell. For example, Notepad would launch my favorite notepad2 program in c:\program files\notepad2\notepad2.exe. So I created a file list shell.list.txt to store them as a sample:

"notepad" "c:\program files\notepad2\notepad2.exe"
"calc" "c:\windows\system32\calc.exe"
"WebDevExpress" "C:\Program Files\Microsoft Visual Studio 9.0\Common7\IDE\VWDExpress.exe"

If this file is located in data sub-directory within the current directory (generally the directory of the current script that is executing), it will be loaded into a Rebol block with this instruction:

shell.list: load %data/shell.list.txt

Then the run function will refer to it to get the real path with the Rebol Select function:

Run: func[exe-path][
  if/else not none? it: select shell.list exe-path [
	call quote it
  ][
        ;in case keyword cannot be found, one supposes it's the full path
	call quote exe-path
  ]
]

Copy and paste it into Rebol Console along with this mock data:

shell.list: ["notepad" "c:\program files\notepad2\notepad2.exe"
"calc" "c:\windows\system32\calc.exe"
"WebDevExpress" "C:\Program Files\Microsoft Visual Studio 9.0\Common7\IDE\VWDExpress.exe"]

So that you can test it by typing

run "c:\windows\system32\calc.exe"

or just the keyword

calc

This latter won’t work. Why? Because calc has not yet been defined as a command in Rebol. To do so, you would create a calc function like this:

calc: func[][
    run "c:\windows\system32\calc.exe"
]

Copy and paste the code above and test calc again, this time it should work.

Now, it would be tedious to define each keyword by creating a new function by hand whereas the procedure is rather generic. So naturally you’d like to use a dynamic generator function to do this for you something like this:

foreach [name path] shell.list [
	func-body: to-block rejoin ['run " " {"}  name {"}]
	set (to-word name) make function! [] func-body
]

If you execute the code above, you could see that it created notepad and calc functions by using the rebol source command:

>> source notepad
notepad: func [][run "notepad"]
>> source calc
calc: func [][run "calc"]
>>

Now if you want to test the calc keyword again, you would get this bad “surprise”:

>> calc
** Script Error: run word has no context
** Where: calc
** Near: run "calc"

because run is an unknown word within the context of func-body you created at runtime within the foreach loop. So you have to bind run to the func-body context by using the bind function like this:

set (to-word name) make function! [] bind func-body 'run

so that you can copy and paste the foreach loop once again:

foreach [name path] shell.list [
	func-body: to-block rejoin ['run " " {"}  name {"}]
	set (to-word name) make function! [] bind func-body 'run
]

Finally typing the calc keyword in Rebol Console should launch the calculator !

To have all this automatically at Rebol launch, put these functions in User.r.

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