4 ms·

Tcl is an interesting little language as well, and the niche it was created for is similar to the one Lua was created for. The biggest advantages that Lua has o

Tcl is an interesting little language as well, and the niche it was created for is similar to the one Lua was created for. The biggest advantages that Lua has over Tcl, off the top of my head, are speed and lambdas. Tcl's semantics make it very hard to optimize because it is stringly typed (with some bytecode and value specialization in the background, but with conversions between strings and other values as needed). Tcl's file system interface is definitely an advantage if you're trying to avoid third party libraries. However, depending on what you need to do with Unicode strings, Lua's strings are "8-bit clean" and have no difficulty storing Unicode characters; Lua's string functions (the pattern-matching functions in particular) aren't Unicode aware.

bch 15y ago
Tcl has lambdas (anonymous functions): http://wiki.tcl.tk/4884 http://wiki.tcl.tk/4884. As of 8.6 (currently in beta), it also has coroutines, and has a non-recursive engine (stackless) among other niceties.
- groovy2shoes 15y ago
  Shows how long it's been since I last used Tcl! Still, Tcl's anonymous functions aren't quite what many people consider to be lambdas: % set inc {x {expr $x + 1}} % apply $inc 1 2 % apply $inc 1 2 % $inc 1 invalid command name "x {expr $x + 1}" % inc 1 1 This works fine with `apply`, but if you treat it like a normal function, it does some strange things. Conversely, functions that are defined with `proc` aren't compatible with `apply` unless you wrap them up. I'm not saying it's inadequate, just that the anonymous functions don't quite work how you expect lambdas to work.
  - bch 15y ago
    I can't speak to what most people expect from lambdas; I force myself use Tcl's [apply] occasionally just to try slightly different paradigms, so I appreciate your commentary. One thing to note though, your final [inc 1] has nothing to do w/ $inc. In the interactive REPL (which I'm assuming you used), Tcl will (by default) essentially autocomplete commands if it can, and [inc] completed to [incr], which is "increment". [incr] adds (by default) 1 to the named variable and returns its result. In this case, the variable name happens to be "1", later accessible via "$1", or [set 1], for example. [edit: I erroneously initially described the "1" in [incr 1] as the integer constant 1; @groovy2shoes reply below reflects my original error. This does go to show another neat feature of Tcl: no keywords.]
    - groovy2shoes 15y ago
      I didn't know that tclsh autocompletes commands; that's pretty neat. In this case, it looks like [incr 1] is incrementing a variable called 1, and appears to start from zero if the variable isn't initialized. I find Tcl's command model interesting because it leads to a very tiny semantics. A few years ago I spent a lot of time thinking about how it could be extended to have lambdas, and I couldn't come up with a way that wouldn't break the command model in some way or another. They aren't something Tcl needs to have, I just thought it'd be convenient. (Tcl's evaluation model allows you to simulate higher-order procs, which, along with `apply`, covers many use cases of lambda).
      - bch 15y ago
        Ya -- interactive tclsh has a few creature-features. The autocomplete we're discussing, automatic fall-through to exec as if via sh(1), command history, history editing, and perhaps more I'm forgetting. kamloops$ tclsh8.6 % info commands up* update uplevel upvar % uptime 7:17PM up 1 hr, 7 users, load averages: 0.06, 0.12, 0.17 % ls fu ls: fu: No such file or directory child process exited abnormally % ls -ld fu ls: fu: No such file or directory child process exited abnormally % ^fu^foo ls -ld foo -rwxr-xr-x 1 joe users 7300 Mar 23 2011 foo % history 1 info commands up* 2 uptime 3 ls fu 4 ls -ld fu 5 ls -ld foo 6 history % !2 uptime 7:20PM up 1:03, 7 users, load averages: 0.13, 0.12, 0.16
        groovy2shoes 15y ago
        > automatic fall-through to exec as if via sh(1) That explains why X11.app launched that one time I forgot a `$` before my `x`...
        bch 15y ago
        That sounds likely. Note that is strictly for interactively typed commands. Witness: kamloops$ cat ls.tcl #!/usr/pkg/bin/tclsh8.6 ls foo kamloops$ ./ls.tcl invalid command name "ls" while executing "ls foo" (file "./ls.tcl" line 3) kamloops$ tclsh8.6 % source ls.tcl invalid command name "ls" % ls foo foo % Now, back to your regularly scheduled Lua topic :)
simon 15y ago
More good points for both sides. This is not making it easier. I don't need speed as I'm doing offline processing and not worried about lambdas at this point. The unicode is important as I am looking to take Greek and Hebrew text and process it.
- groovy2shoes 15y ago
  You may be better off with Tcl, then, if you don't want to use a library for Unicode.
  - simon 15y ago
    It's not so much that I don't want to use a library, but more that I would be unable to use much of the core language for the processing and would have to do everything in/with the library and store my text in Unicode-aware holders rather than just strings. If that's how it ends up, then so be it, but I'll try TCL first and know that I have Lua as a reasonable fall back plan.

bch 15y ago

Tcl has lambdas (anonymous functions): http://wiki.tcl.tk/4884 http://wiki.tcl.tk/4884. As of 8.6 (currently in beta), it also has coroutines, and has a non-recursive engine (stackless) among other niceties.

groovy2shoes 15y ago
Shows how long it's been since I last used Tcl! Still, Tcl's anonymous functions aren't quite what many people consider to be lambdas: % set inc {x {expr $x + 1}} % apply $inc 1 2 % apply $inc 1 2 % $inc 1 invalid command name "x {expr $x + 1}" % inc 1 1 This works fine with `apply`, but if you treat it like a normal function, it does some strange things. Conversely, functions that are defined with `proc` aren't compatible with `apply` unless you wrap them up. I'm not saying it's inadequate, just that the anonymous functions don't quite work how you expect lambdas to work.
- bch 15y ago
  I can't speak to what most people expect from lambdas; I force myself use Tcl's [apply] occasionally just to try slightly different paradigms, so I appreciate your commentary. One thing to note though, your final [inc 1] has nothing to do w/ $inc. In the interactive REPL (which I'm assuming you used), Tcl will (by default) essentially autocomplete commands if it can, and [inc] completed to [incr], which is "increment". [incr] adds (by default) 1 to the named variable and returns its result. In this case, the variable name happens to be "1", later accessible via "$1", or [set 1], for example. [edit: I erroneously initially described the "1" in [incr 1] as the integer constant 1; @groovy2shoes reply below reflects my original error. This does go to show another neat feature of Tcl: no keywords.]
  - groovy2shoes 15y ago
    I didn't know that tclsh autocompletes commands; that's pretty neat. In this case, it looks like [incr 1] is incrementing a variable called 1, and appears to start from zero if the variable isn't initialized. I find Tcl's command model interesting because it leads to a very tiny semantics. A few years ago I spent a lot of time thinking about how it could be extended to have lambdas, and I couldn't come up with a way that wouldn't break the command model in some way or another. They aren't something Tcl needs to have, I just thought it'd be convenient. (Tcl's evaluation model allows you to simulate higher-order procs, which, along with `apply`, covers many use cases of lambda).
    - bch 15y ago
      Ya -- interactive tclsh has a few creature-features. The autocomplete we're discussing, automatic fall-through to exec as if via sh(1), command history, history editing, and perhaps more I'm forgetting. kamloops$ tclsh8.6 % info commands up* update uplevel upvar % uptime 7:17PM up 1 hr, 7 users, load averages: 0.06, 0.12, 0.17 % ls fu ls: fu: No such file or directory child process exited abnormally % ls -ld fu ls: fu: No such file or directory child process exited abnormally % ^fu^foo ls -ld foo -rwxr-xr-x 1 joe users 7300 Mar 23 2011 foo % history 1 info commands up* 2 uptime 3 ls fu 4 ls -ld fu 5 ls -ld foo 6 history % !2 uptime 7:20PM up 1:03, 7 users, load averages: 0.13, 0.12, 0.16
      - groovy2shoes 15y ago
        > automatic fall-through to exec as if via sh(1) That explains why X11.app launched that one time I forgot a `$` before my `x`...
        bch 15y ago
        That sounds likely. Note that is strictly for interactively typed commands. Witness: kamloops$ cat ls.tcl #!/usr/pkg/bin/tclsh8.6 ls foo kamloops$ ./ls.tcl invalid command name "ls" while executing "ls foo" (file "./ls.tcl" line 3) kamloops$ tclsh8.6 % source ls.tcl invalid command name "ls" % ls foo foo % Now, back to your regularly scheduled Lua topic :)

simon 15y ago

More good points for both sides. This is not making it easier. I don't need speed as I'm doing offline processing and not worried about lambdas at this point. The unicode is important as I am looking to take Greek and Hebrew text and process it.

groovy2shoes 15y ago
You may be better off with Tcl, then, if you don't want to use a library for Unicode.
- simon 15y ago
  It's not so much that I don't want to use a library, but more that I would be unable to use much of the core language for the processing and would have to do everything in/with the library and store my text in Unicode-aware holders rather than just strings. If that's how it ends up, then so be it, but I'll try TCL first and know that I have Lua as a reasonable fall back plan.