Talk:Execute a Markov algorithm: Difference between revisions

I just slapped together the [[Markov Algorithm#J|J solution]] in 20 seconds, so it doesn't fully implement a Markov evaluator. In particular, it doesn't handle terminating rules; there may be other small wrinkles, but that depends on how one interprets the (underspecified) BNF grammar. All would be trivial to fix, but I don't have time now. Anyway, here are the gaps I think of:▼

# Terminating rules are not handled. The fix is easy but would involve modification or duplication of a standard function, [http://www.jsoftware.com/trac/base/browser/branches/cdb/main/main/strings.ijs?rev=418#L239 stringreplace].▼

# Similarly, according to [[wp:Markov algorithm|WP]], <blockquote> if [a rule is matched], replace the '''leftmost''' matching text in the input string with its replacement in the first applicable rule.</blockquote> But stringreplace will replace '''all''' instances of matches at once. Again, a trivial fix as long as we're willing to reprise stringreplace.▼

# <s>The standard function [http://www.jsoftware.com/trac/base/browser/tags/j601c/api/regex/regex.ijs?rev=322&order=date#L130 rxcut] will cut on all <code>\s+->\s+</code> though the grammar calls for ignoring any of these after the first (so the replacement string may carry a <code>-></code>). Fix is trivial, where we'd probably use <code>rxE</code>instead.</s> Silly, we can just use <code>rxmatch</code> rather than <code>rxmatch'''es'''</code>. --[[User:DanBron|DanBron]] 17:47, 15 December 2009 (UTC)▼

# Note also that leading blanks in the rule and trailing blanks in the replacement are removed -- the grammar doesn't call for this. Very trivial fix.▼

I just realized it took me longer to write up the description of these gaps than it would've taken me to fix them. :P --[[User:DanBron|DanBron]] 16:27, 15 December 2009 (UTC)▼