[sreque]

It's worse than that, unfortunately. Everything is implicitly convertible to a string, and every string is implicitly convertible to any other type. So, if you pass a dictionary into your function that expects a list, it will happily convert between types for you. I do not like this sort of behavior in my dynamic type system.

[marshray]

(Apologies in advance, I'm just thinking out loud here, not meaning to troll.)

So you like strong typing. I do too, but I like it even more at compile time. If you're doing without the compile time error checking, why not go all the way and do without type errors at runtime as well? Sounds like a choice between:

1. type errors at compile time,

2. data-dependent type errors at runtime, or

3. data-dependent corruption and/or non-type errors at runtime.

[luser001]

> I do not like this sort of behavior in my dynamic type system.

Why? [Other than for performance reasons]

I keep repeating this point in every Tcl thread. Tcl was meant to be used to enable command line shells for programs written in C.

Btw, being able to treat a list as a dict has been useful to me. I (developer) write a routine to be used by a non-developer, who may not be a great programmer. The list notation is easy in Tcl. I can just tell them to make a list with keys and values alternating. And for a one-time conversion cost, I get to use it as a dict.

Also works the other way around: I can return a dict. And if a Blub user is processing it, he's free to ignore my documentation that it's a dict and process it as a list (again for a one-time cost).

YMMV.

[masklinn]

> Why? [Other than for performance reasons]

Because it becomes very hard to reason with what you have at hand, and in my experience the "helpful" conversions, rather than actually help, mostly hides errors and bugs in the code and delays there effect, making them much harder to diagnose than a stricter handling.

[RHSeeger]

Tcl's EIAS can be annoying at times, but it also allows for an amazingly easy to use language that provides for some amazingly powerful abilities. For example, the ability to build arbitrary control structures with little effort. Most other languages, dynamic or not, can't come close to it's flexibility and some of the things you can do with it.

[jjr]

But a dict is a list of paired elements? I do like the fact that you can convert freely between string/list/dict. It removes a lot of boilerplate type conversion. Want to serialize a dict? In most languages that's boring code. In Tcl it's so easy you do it all the time.

[skoob]

> But a dict is a list of paired elements?

Not really. A dict is an unordered set of keys where each key has a value associated with it. If you try to access a dict as a list, you might expect to get a list of key-value pairs or a list of values or possibly a list of keys. And in what order will the elements in the list be?

[schlenk]

Tcl dicts are ordered, so you have a defined order for this. http://www.tcl.tk/man/tcl/TclCmd/dict.htm#M27

[keypusher]

Depends on the language, but I prefer the Python approach here. Python is a dynamically (but strongly) typed language. If you want a list from a dict, get a new list via casting ie. list(the_dict), or get a list from either side via the_dict.keys() or the_dict.values(). Weakly typed languages that will do implicit type conversion for you such as TCL and Perl seems prone to mistakes and confusion from this stuff as code complexity of the project grows. I don't think Python gets it right here either though really, as in the end explicit types save so much headache and stupid bugs by finding problems for you at lint or compile time.