Please could some wonderfully compassionate Perl Monk please read this script and tell me what the problem is. I have explained what I am doing using comments in the script itself. See line final comment for the problem. I have two csv files, one of them, fruit.csv, contains apples,5 in the first row, and the other, fruit_names.csv, simply contains apples in the first row. I create a hash, %fruit, with a single key value pair, (apples 5), which are both read from fruit.csv. I then read "apples" from the first line of fruit_names.csv, and use this as the key to access the value from %fruit, hoping to get the value 5. But this DOES NOT WORK. Why is this? 



my %fruit; # create hash 

open(FRUIT, "fruit.csv"); 
while(<FRUIT>){
@line = split (",", $_); 
$fruit_name = $line[0]; # the value of this is obviously apples
$number = $line[1]; # the value of this is 5
$fruit{$fruit_name} = $number; # puts key-value pair (apples 5) into t
+he hash
}
close(FRUIT);


open(FRUITNAMES, "fruit_names.csv"); 
while(<FRUITNAMES>){
@line = split (",", $_);
$thefruitsname = $line[0]; # the value of this is apples
$thenumber = $fruit{$thefruitsname}; 

print "the number of $thefruitsname is $thenumber\n";
# this prints "the number of apples is   " (WHY does this not work? NB
+ if I change $thefruitsname to "apples" (without quotation marks) the
+n it does print "the number of apples is 5".)
}

[download]

Background: the file fruit_names.csv will actually contain a very long list of fruit names in a particular order. The file fruit.csv will contain a much shorter list of fruit names and numbers. I want to create a list of all the fruit in this list, with their numbers, in the same order as the fruit names appear in fruit_names.csv including empty rows for fruits which do not appear in fruit.csv but which are in fruit_names.csv. This is because I have data for the amount of each fruit sold on average per week in ten different stalls, but each list of fruit (and numbers) is in a different order and doesn't contain all of the same fruits (but all fruit ARE listed in fruit_names.csv). In order to compare the ten lists, I want to create a table with all the possible fruit names in the leftmost column, and a column for each stall showing number of each fruit sold, or blank if no data exist for that fruit.

In reply to Getting values from a hash, using a string taken from a .csv file as the value by AnnaSpanner

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