Re: using hashes

and iterate through all the hash keys

Don't ever iterate hash keys! (Well, hardly ever :)

The major purpose of hashes is that you can lookup the value associated with any key directly, avoiding iteration.

For your purpose, the major part of the code should be something like:

while( <$names_to_be_replaced_file> ) {    ## read each line
    s[\b([a-z]+)\b][ $name_id{ $1 } ]ge;   ## find words, look them up
+ and replace them with the id
    print;                                 ## Send the modified lines 
+to stdout
}
[download]

Simple and very efficient.

With the rise and rise of 'Social' network sites: 'Computers are making people easier to use everyday'

Examine what is said, not who speaks -- Silence betokens consent -- Love the truth but pardon error.

"Science is about questioning the status quo. Questioning authority".

In the absence of evidence, opinion is indistinguishable from prejudice.

Comment on Re: using hashes Download Code

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Re^2: using hashes by R56 (Sexton) on Sep 26, 2013 at 16:51 UTC
Thanks for the help Browser, but apparently I'm way behind in Perl knowledge yet, as I don't really get the code... That's how I know I'm overcomplicating something that is really simple :\| Is the $1 var pointing to the value of the hash?	[reply]
Re^3: using hashes by BrowserUk (Patriarch) on Sep 26, 2013 at 17:09 UTC
Is the $1 var pointing to the value of the hash? `$1` captures the words in the string one at a time. This `$hash{ $1 }` looks that word up in the hash and returns the associates value (id). The `ge` causes the ids to be substituted for every word in the line. Perhaps this will clarify things? `%hash = ( brown=>1, fox=>2, quick=>3, the=>4 );; $line = 'the quick brown fox';; $line =~ s[\b([a-z]+)\b][ $hash{ $1 } ]ge;; print $line;; 4 3 1 2` [download] With the rise and rise of 'Social' network sites: 'Computers are making people easier to use everyday' Examine what is said, not who speaks -- Silence betokens consent -- Love the truth but pardon error. "Science is about questioning the status quo. Questioning authority". In the absence of evidence, opinion is indistinguishable from prejudice.	[reply] [d/l] [select]
Re^4: using hashes by R56 (Sexton) on Sep 26, 2013 at 18:21 UTC
Yes, it did! Your solution combined with Kenneth's apparently did the trick. Will try to work around it a little bit tho, see if I can make it quicker. Thanks for the help :)	[reply]
Re^3: using hashes by hdb (Monsignor) on Sep 26, 2013 at 17:30 UTC
In order to make things even more complicated I recommend to replace `$hash{ $1 }` with `$hash{ $1 } // $1` [download] which means if `$1` is not found in your hash, then replace your word with itself, ie leave it unchanged.	[reply] [d/l] [select]
Re^3: using hashes by aaron_baugher (Curate) on Sep 26, 2013 at 17:16 UTC
`s[\b([a-z]+)\b][ $name_id{ $1 } ]ge;` The 's' at the beginning says to find a pattern and replace it. The 'g' at the end says to repeat this process as many times as possible. The 'e' at the end says that the replacement part should be evaluated as code, not treated as literal text. In the first part, the pattern, the \b matches a "word boundary," the boundary between word characters and non-word characters like your commas. `[a-z]+` means a string of 1 or more consecutive lowercase letters. The parentheses around that capture whatever is matched within them and save it in the special variable $1. In the replacement part, $1 contains the matched word, so this becomes a simple lookup for that word as a key in the `%name_id` hash, replacing it with the value corresponding to that key. As mentioned before, because of the 'g', this entire process is repeated for each match found in the line. Aaron B. Available for small or large Perl jobs; see my home node.	[reply] [d/l] [select]