Perldoc perlobj states:

Sometimes you want to call a method when you don't know the method name ahead of time. You can use the arrow form, replacing the method name with a simple scalar variable containing the method name

But what about when you know part of the method name ahead of time, just not all of it? I want to call a method using some known text plus a scalar variable. For example, see the method called on "$caller" in either of the following, neither of which works:

 $$database_handle = DBI->connect(map {exists $arguments{$_} ? $argume
+nts{$_}  : $caller->"database_${_}"()} qw(data_source_name username p
+assword taint)) or die "Could not connect to the database: $DBI::errs
+tr";

[download]

... produces the error ...

String found where operator expected at Storage.pm line 46, near "->"d
+atabase_${_}"" (Missing operator before "database_${_}"?)

[download]

... or maybe this will work ...

  $$database_handle = DBI->connect(map {exists $arguments{$_} ? $argum
+ents{$_}  : $caller->database_$_()} qw(data_source_name  username pas
+sword taint)) or die  "Could not connect to the database: $DBI::errst
+r";

[download]

... nope ...

Scalar found where operator expected at Storage.pm line 47, at end of 
+line  (Missing operator before ?)
syntax error at Storage.pm line 47, near "->database_$_"

[download]

The only way I have found to make this work -- after several SuperSearches and trying perl5.6 and perl5.8 -- is to create a new simple scalar variable and use this as the method call, as such:

  $$database_handle = DBI->connect(map {my $s="database_$_";exists $ar
+guments{$
_} ? $arguments{$_} : $caller->$s()} qw(data_source_name username pass
+word taint)) or die "Could not connect to the database: $DBI::errstr"
+;

[download]

The above code compiles fine. It is a bit kludgy though. Is there any way to accomplish a method call that mixes an interpolated variable and some known text, sort of like a double quoted string?

In reply to Double quoted string as method call by ryantate

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