February 1999
- client images Chris Gray
- Question on c++ switch optimization, and parsers in general. Ben Greear
- Question on c++ switch optimization, and parsers in general. Adam Wiggins
- Question on c++ switch optimization, and parsers in general. Ola Fosheim Grøstad
- Question on c++ switch optimization, and parsers in general. Chris Gray
- Question on c++ switch optimization, and parsers in general. Chris Gray
- Question on c++ switch optimization, and parsers in general. T. Alexander Popiel
In message: <199902090353.UAA00877@ami-cg.GraySage.Edmonton.AB.CA>
Chris Gray <cg@ami-cg.GraySage.Edmonton.AB.CA> writes:
>
>However if you insist on minimal unambiguous abbreviations, and don't
>want a linear search, how about this:
>
>At startup time, scan your table of commands, and build some auxilliary
>data structures. Have the code determine the minimum unambiguous form
>of all commands. Enter all of those into a hash table (could even try
>a mostly minimal one). Include in your data structures the full name
>of the commands. Then, lookup consists of looking up longer and longer
>portions of the input command until you find a match, or you have tried
>the full command. Search is O(length of input command) rather than
>O(number of commands).
Better yet, just store your commands in a compressed radix tree.
(Treat the command string as a bit string, going left or right
based on 0 or 1 in a given position; when building the tree,
omit levels where there is no branch. Internal tree nodes tell
which bit to test, commands are in leaves. You can optimize
by testing more than 1 bit at a time and having a larger branching
factor.) Just walk the tree until you reach the end of input
or hit a leaf. If you run out of input before reaching a leaf,
then the input was ambiguous. If you reach a leaf, check the
input against the command you found, to see if they typed garbage
which just looked somewhat like a command (weird things can happen
with the tree compression). If you're using a higher branching
factor and walk off the tree, then they entered a bogus command.
Search is at most O(length of input command) (and is frequently
less), typos tend to fail early instead of testing every possible
prefix, and you don't have to reprobe a hash table or figure out
minimum non-ambiguity. The tree-insert code is a bit of a pain,
though.
- Alex
- Question on c++ switch optimization, and parsers in general. T. Alexander Popiel
- Question on c++ switch optimization, and parsers in general. Ola Fosheim Grøstad
- Question on c++ switch optimization, and parsers in general. Richard Woolcock
- Question on c++ switch optimization, and parsers in general. Marc Hernandez
- Question on c++ switch optimization, and parsers i Chris Gray
- Question on c++ switch optimization, and parsers i Jon A. Lambert
- Question on c++ switch optimization, and parsers i Chris Gray
- optimizing code diablo@best.com
- optimizing code Hans-Henrik Staerfeldt
- optimizing code Chris Gray
- code profiling Chris Gray
- World-file parsing and RTTI? The Arrow
- World-file parsing and RTTI? Mark Gritter
- pet peeves diablo@best.com
- pet peeves diablo@best.com
- pet peeves Caliban Tiresias Darklock
- pet peeves Marc Bowden
- pet peeves Richard Woolcock
- pet peeves Koster, Raph
- pet peeves diablo@best.com
- pet peeves Caliban Tiresias Darklock
- pet peeves Kristen Koster
- pet peeves Caliban Tiresias Darklock
- pet peeves Adam Wiggins
- pet peeves Wes Connell
- pet peeves J C Lawrence
- pet peeves Matthew Mihaly
- pet peeves Ling
- pet peeves Ola Fosheim Grøstad
- pet peeves Matthew Mihaly
- pet peeves Ola Fosheim Grøstad
- pet peeves Matthew Mihaly
- pet peeves David Bennett
- pet peeves Robert Woods
- pet peeves Wes Connell
- pet peeves Travis S. Casey
- pet peeves Matthew Mihaly
- pet peeves Neerenberg, AaronX
- pet peeves greg
- pet peeves Richard Woolcock
- pet peeves J C Lawrence
- pet peeves Martin Keegan
- pet peeves Ola Fosheim Grøstad
- pet peeves J C Lawrence
- pet peeves diablo@best.com
- pet peeves Brandon A Downey
- pet peeves diablo@best.com
- pet peeves Darren Henderson
- pet peeves diablo@best.com
- pet peeves Darren Henderson
- pet peeves Steve Houchard
- pet peeves diablo@best.com
- pet peeves Darren Henderson
- pet peeves diablo@best.com
- pet peeves Steve Houchard
- pet peeves diablo@best.com
- pet peeves Richard Woolcock
- pet peeves diablo@best.com
- pet peeves Richard Woolcock
- pet peeves Apocalypse
- pet peeves Caliban Tiresias Darklock
- pet peeves diablo@best.com
- pet peeves Adam Wiggins
- pet peeves diablo@best.com
- pet peeves Adam Wiggins
- pet peeves diablo@best.com
- pet peeves Mik Clarke
- pet peeves Caliban Tiresias Darklock
- pet peeves Travis S. Casey
- pet peeves Caliban Tiresias Darklock
- pet peeves Benjamin D. Wiechel
- pet peeves Marc Bowden
- pet peeves Matthew Mihaly
- pet peeves Mik Clarke
- pet peeves Benjamin D. Wiechel
- pet peeves Matthew Mihaly
- pet peeves Caliban Tiresias Darklock
- pet peeves Marc Bowden
- pet peeves Matthew Mihaly
- pet peeves David Bennett
- pet peeves David Bennett
- pet peeves Petri Virkkula
- pet peeves J C Lawrence
- Horror Themed Muds [was CthulhuMud Driver 6] Christopher Allen
- Horror Themed Muds [was CthulhuMud Driver 6] Caliban Tiresias Darklock
- Horror Themed Muds [was CthulhuMud Driver 6] Mik Clarke
- CthulhuMud Driver 6 Mik Clarke
- CthulhuMud Driver 6 J C Lawrence
- Mathengine Ling
- Mathengine Apocalypse
- Website update Koster, Raph
- Influential muds Koster, Raph
- Influential muds Dan Shiovitz
- Influential muds Adam Wiggins
- Influential muds Sunny Gulati
- Influential muds diablo@best.com
- Influential muds Juha Lindfors
- Influential muds Brandon J. Rickman
- Influential muds Caliban Tiresias Darklock
- Influential muds Andy Cink
- Influential muds J C Lawrence
- Influential muds Dr. Cat
- Influential muds Jay Carlson
- Influential muds Mik Clarke
- Influential muds Richard Woolcock
- Influential muds Koster, Raph
- Influential muds Mik Clarke
- Influential muds Ola Fosheim Grøstad
- Influential muds Dan Root
- Influential muds Benjamin D. Wiechel
- State of the art? Andy Cink
- State of the art? diablo@best.com
- State of the art? Caliban Tiresias Darklock
- State of the art? ##Make Nylander
- State of the art? diablo@best.com
- State of the art? Martin Keegan
- State of the art? David Bennett
- State of the art? Martin Keegan
- State of the art? Andy Cink
- State of the art? J C Lawrence
- State of the art? David Bennett
- State of the art? Matthew Mihaly
- State of the art? Caliban Tiresias Darklock
- State of the art? Matthew Mihaly
- State of the art? Ola Fosheim Grøstad
- State of the art? Ola Fosheim Grøstad
- State of the art? J C Lawrence
- State of the art? Matthew Mihaly
- State of the art? Mik Clarke
- State of the art? J C Lawrence
- The Terrorist Class Ola Fosheim Grøstad
- The Terrorist Class Mik Clarke
- Welcome To "MUD-Dev"! mud-dev-admin@kanga.nu
- IMPORTANT ADMIN: New list setup requires your attention J C Lawrence
- ADMIN: URL change J C Lawrence
- PermaDeath (was pet peeves) Marc Hernandez
- ScryMUD 1.8.7 released. Ben Greear
- PermaDeath Sayeed
- PermaDeath Ola Fosheim Grøstad
- PermaDeath Sayeed
- roleplaying and immersion (was: PermaDeath) Ola Fosheim Grøstad
- Roleplaying and Immersion (was: PermaDeath) Sayeed
- Roleplaying and Immersion (was: PermaDeath) Adam Wiggins
- Roleplaying and Immersion (was: PermaDeath) J C Lawrence
- Roleplaying and Immersion (was: PermaDeath) Ola Fosheim Grøstad
- WEB: VR-stuff Ola Fosheim Grøstad
- WEB: VR-stuff J C Lawrence
- WEB: VR-stuff Mik Clarke
- WEB: VR-stuff Marian Griffith
- WEB: VR-stuff J C Lawrence
- ADMIN: The list archives are now online and fully searchable J C Lawrence
- Theories was pet peeves Wes Connell