On Dec 5, 4:49 pm, Johnathan S. [email protected] wrote:
hey guys
sorry for the whole mix up! I appreciate all the help I’ve received
especially as im new to ruby! im also new to the forum and should have
tried to stick it our with the first threat! so i hope i havn’t offended
any of you by this.
Nah! Any mistake you might make, we’ve already done that and worse
(probably several times). 
that aside, i really hope you can help me resolve this problem.
Jordan, the code you gave me worked successfully. However, it just deals
with the the two types i gave you, author and type.Its partially my
fault for not explaining properly becuase i hope it could deal with any
information after the tag. is this possible to achieve?
Sure it is. The code I gave you can be expanded, but it was mainly
just for you to get started with, because it is fragile (as you saw
from my mis-post). Even with the correct “author[8…-1]”, if you
accidentally leave out the space between the “Author: Name” line, it
will still clip the first letter off the name ([number…number] means
to grab a smaller section from a larger container, and -1 has the
special meaning of the last item; so author[8…-1] means to get the
characters from number 8 to the end).
What you really want is something more flexible, that will allow for
those kinds of mistakes and still do the right thing in almost every
case. That is a regular expression. It lets you give it a pattern
which has certain rules, and matches a string in different ways based
on those rules. And this is just what Phrogz’ code is doing:
we’ll get rid of linecount since you can
get that information directly from your hash
and we’ll store the hashes as subhashes
underneath a main one, keyed by “Tag:” value
database = {}
File.open(‘reference.txt’) { | handle |
last_tag = nil # we’ll use this to keep track of
# the last tag we’ve seen, see below
handle.each { | line |
# the following regexp says to match:
# ^ = starting at the first char
# (\w+) = 1 or more "word" characters (a-z / 0-9)
# : = followed by a literal colon
# \s* = then zero or more "space" characters
# ([\w+,\s]+) = 1 or more "word/space/," characters
# $ = with nothing else until the end of line
#
# any string meeting that criteria is a match and m is
# the match data, however if the string doesn't match
# e.g., a blank line, m is nil
m = line.match(/^(\w+):\s*([\w+,\s]+)$/)
if m # if m is a match (i.e., not nil)
if m[1] == 'Tag' # we want to add a key to the hash
# since this is a "Tag:" line
# when we used the () in the regexp
# that told ruby we only care about
# those chars, and we can access
# them in the match object with m[n]
# i.e, m[1] means whatever part of the
# line matched (\w+)
last_tag = m[2].chomp
database[last_tag] = {} # make a subhash as the value
# now we have, e.g.,
# database["ref1"] = {}
else
# it's not a "Tag:" line, so we add it as key, value
# to the subhash we created for the last tag key we
# created in the hash
database[last_tag][m[1].downcase] = m[2].chomp
# e.g., database["ref1"]["type"] = "Journal"
end
end
}
}
now print it
print "# of Tags: ", database.length, “\n\n”
print "Contents: ", database.inspect, “\n\n”
puts database[“ref2”][“author”]
========
This outputs:
of Tags: 3
Contents: {“ref1”=>{“author”=>“Little, S R”, “type”=>“Book”},
“ref2”=>{“author”=>“Smith, J”, “type”=>“Journal”},
“ref3”=>{“author”=>“Williams, M”, “type”=>“Conference Paper”}}
Smith, J
again sorry for the mix up
cheers
–
Posted viahttp://www.ruby-forum.com/.
No worries
HTH,
Jordan