Removed the limit on the number of traces in dumpVCD

[marijn-qbaylogic]

dumpVCD was limited to 93 traces, because it could only generate single character trace identifier codes. The codes are now generated ad infinitum, and the restriction has been removed.

Fixes: #3082

Still TODO:

• Check copyright notices are up to date in edited files

[DigitalBrains1]

How about this instead:

Suggested change

	labels = "!" : map go [1..]
	where
	go 0 = ""
	go n = chr ( 33 + n `mod` k) : go (n `div` k)
	k = 126-33+1
	labels = concatMap (\s -> map (snoc s) alphabet) ([]: labels)
	where
	alphabet = map chr [33..126]

You'll need to import

import Data.List.Extra (snoc)

[marijn-qbaylogic]

This is one fancy way of doing things.
Are there specific things that make it better? I do agree it's better, but there might be stuff I am missing.

[DigitalBrains1]

If the alphabet were "abc", this is what it would generate:

>>> import Text.Show.Pretty 
>>> pPrint $ P.take 20 labels
[ "a"
, "b"
, "c"
, "aa"
, "ab"
, "ac"
, "ba"
, "bb"
, "bc"
, "ca"
, "cb"
, "cc"
, "aaa"
, "aab"
, "aac"
, "aba"
, "abb"
, "abc"
, "aca"
, "acb"
]

It is almost how a base-n number system would work, except that 0 is also significant in leading positions. It just seems like a clean numbering to me.

It's also more Haskelly if you ask me :-).

[DigitalBrains1]

The recursion step of the algorithm in words is roughly this:

To form all labels of length up to n+1 we take all labels up to a length n and for all of those labels and all letters of the alphabet, we append the letter of the alphabet to the label. Also, for each letter of the alphabet, include just that letter as a label (because by increasing the length of all labels we lost the labels of length 1 plus we clearly need to start somewhere).

[DigitalBrains1]

This file seems to use ++ for concatenating strings, in the interest of consistency I'd like to see that maintained here.

[marijn-qbaylogic]

Looking at these lines, why do we even add a newline? It isn't there a few lines later:

format n label (mask,val) =
  "b" ++ map digit (reverse [0..n-1]) ++ " " ++ label

[DigitalBrains1]

You're completely right, they don't need a newline! It's already handled in two Text.intercalate "\n"s. Let's remove it.