@Ronnie
Vielfachen drachlichen Dank.
Ich konnte mich nämlich nicht mehr genau entsinnen, was das war.
QuoteA literal of the form v1.20.300.4000 is parsed as a string composed of characters with the specified ordinals. This provides an alternative, more readable way to construct strings, rather than use the somewhat less readable interpolation form "\x{1}\x{14}\x{12c}\x{fa0}". 
This is useful for representing Unicode strings, and for comparing version ``numbers'' using the string comparison operators, cmp, gt, lt etc. If there are two or more dots in the literal, the leading v may be omitted.
    print v9786;              # prints UTF-8 encoded SMILEY, "\x{263a}"
    print v102.111.111;       # prints "foo"
    print 102.111.111;        # same
in perldata von 5.6.1
Ja, in perdata steht es. Aber useful!?? Nein.
Kein Wunder dass bei 5.8 steht:
QuoteThe marginal benefits of v-strings were greatly outweighed by the potential for Surprise and Confusion.
QuoteNote that since Perl 5.8.1 the single-number v-strings (like v65 ) are not v-strings before the => operator (which is usually used to separate a hash key from a hash value), instead they are interpreted as literal strings ('v65'). 
Das hatte ich aber erwartet.
Kein Wunder, dass ich darüber fiel. Noch keine v-strings benutzt.
Also besser solche Keys in einfache Anführungszeichen.
Böse Falle.\n\n
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