Transparent filter for stdin and stdout that collects lines consisting of a Cult of the Bound Variable encrypted publication strings that appear in the output of running the ICFP-2006 Universal Machine and stores them in a file whose name is specified as the only command line argument.

Pipe the output of the um into it, e.g.:

rum main.um | clueslurp cbvpubs.txt

Note that duplicates are not removed yet so in the mean time use this:

sort cbvpubs.txt |uniq >cbvpubs-unique.txt

In the beforetime there was a program called expect which was good for driving interactive consoles with stuff like sending characters, waiting to receive certain input and some other programming-language-like stuff. What follows is an idea for a minimalist system with a similar design.

MINI SPOILER: In the contest, the first thing you realise when you boot the VM is that there are various user accounts that you have to login as in the virtual machine in order to discover the component puzzles. So you want to login as a specific user, interact, possibly capture output or send input read from a file or from executing a child process and then exit.

A few implementation ideas:

• A config file for this filter which can drive the interaction, enabling programmatic automation.
• An API which can be used in GHCi.
• Use socat or something clever Modify the filter to provide a server socket over which programmatic interaction can be tapped by possibly multiple programs independently

Config file for driving the console interaction, format consists of the following syntax.

• lines prefixed with # and blank lines are ignored in processing
• don't make parsing harder by accidentally making white space significant
• if there is something similar that already exists us that instead, possibly a mini language that is more general but which could be easily adapted to the character-oriented filter situation?

line 
  : '#' text 
  | cmd
cmd  
  : output
  | await_literal
  | await_regex
  | await_negated_regex
  | set_variable
output 
  : '>' text
await_literal
  : '<' text
await_regex
  : '/' regex
await_negated_regex
  : '^' regex
regex
  : text ['/' regex_options]
set_variable
  : '=' name value_expression
value_expression
  : regex_capture_group
  | 

Maybe it would be cool to implement the functionality of the filter in this more general language. Need to be able to specify an action like append a line that matches a regex to a file.

The config for this might look something like the following. Match a publication regex and if found, append the whole match to the file with the given name. Indentation is for human only.:

# open paren groups trigger followed by sequence of actions
# regex capture group $0 is whole match
(
# look for publications
/ <publication_regex>
  # append whole match to file with given name
  + $0 "publications.txt"
)

Other commands could be:

• f filename start capturing output to file
• F filename start capturing output to file in append mode
• r filename send content of file as guest's stdin
• ! command send output of running command (variable substitution...)
• s float sleep float seconds`
• x close stream, exit
• d filename dest download filename to host dest using umix facility
• u filename dest upload host filename to umix dest using umix facility
• Macro facility?
• parenthetic command grouping?

Could have predefined variables like current user, command history, runtime etc.

Can some hacked up script and socat cover this sort of feature set without all this implementation work?