G'day Rolf,

"tested in 5.10

could someone plz test in newer versions and reply?"

Same result in 5.14.2:

$ perl -e '$a=inf; print ++$a,"\n"'
ing

$ perl -v

This is perl 5, version 14, subversion 2 (v5.14.2) built for darwin-th
+read-multi-2level
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As you were probably aware, warnings alert you and strictures disallow it altogether:

$ perl -Mwarnings -e '$a=inf; print ++$a,"\n"'
Unquoted string "inf" may clash with future reserved word at -e line 1
+.
ing

$ perl -Mstrict -e '$a=inf; print ++$a,"\n"'
Bareword "inf" not allowed while "strict subs" in use at -e line 1.
Execution of -e aborted due to compilation errors.
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