I have a long text file (a tab-file for stardict-editor) which consists of lines in the following format:
word1 some text word1 some other text word2 more text word3 even more
and would like to convert it to
word1 some text<br>some other text word2 more text word3 even more
This means that subsequent lines (the file is sorted) which start with the same word should be merged to a single one (here the definitions are separated with
<br>). Lines with equal beginning can also appear more often than just twice. The character which separates word and definition is a tab-character and is unique on each line.
word3 are of course placeholders for something arbitrary (except tab and newline characters) which I don't know in advance.
I can think of a longer piece of Perl code which does this, but wonder if there is a short solution in Perl or something for the command line. Any ideas?