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Comment by multiply | Hacker News Reader

My worst experience was doing a simple min/max of each signal took 7x longer than the simulation. I'd be so happy to toss TCL in the trash. I spent a long time debugging because TCL expr doesn't do -2^2 correctly. The error messages don't tell you the line number and I found no good way to debug. Things like that are just the tip of the iceberg of time wasted fighting with arcane tools. I suppose others have their own stories.

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In Tcl's expr:

^ stands for bitwise XOR: so [expr {-2^2}] results in -4

* stands for exponentiation: so [expr {-2*2}] results in 4

Both seem correct to me, taking into account how integers are represented in binary (two's complement for the negative ones).

With regards to debugging dynamic programming languages, it is different as compared to their static counterparts, since much is delayed to happen at runtime (as opposed to at compilation time). But it also opens up possibilities (like introspection, ability to intervene in the scripts while they run, ...). It requires a different mindset.

I've always been astounded that much of the rage against Tcl seems to stem from the fact that it works as documented, rather than according to the rules of other languages.

Mmmn, HN stripped out the half of the double asterisks, now I made it confusing myself... Too late to edit my comment above, but it needs to be like this:

** stands for exponentiation: so [expr {-2**2}] results in 4

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