You can use Text::MicroMason:

  use Text::MicroMason::Functions qw( execute );
  $template = "bar <% $ARGS{var1} %> foo <% $ARGS{var2} %> bar BAAAR!"
+;
  $output = execute( $template, var1=>"Guybrush", var2=>"Purcell" );
[download]

If it will be used repeatedly, you can pre-compile your template for faster execution:

  use Text::MicroMason::Functions qw( compile );
  $template = "bar <% $ARGS{var1} %> foo <% $ARGS{var2} %> bar BAAAR!"
+;
  $subroutine = compile( $template );
  $output = $subroutine->( var1=>"Guybrush", var2=>"Purcell" );
[download]

There's also an object-oriented interface:

  use Text::MicroMason;
  $interpreter = Text::MicroMason->new();
  $template = "bar <% $ARGS{var1} %> foo <% $ARGS{var2} %> bar BAAAR!"
+;
  $subroutine = $interpreter->compile( $template );
  $output = $subroutine->( var1=>"Guybrush", var2=>"Purcell" );
[download]

You can swap in a different syntax if desired:

  use Text::MicroMason;
  $interpreter = Text::MicroMason->new( -TextTemplate );
  $template = "bar { $var1 } foo { $var2 } bar BAAAR!";
  $subroutine = $interpreter->compile( $template );
  $output = $subroutine->( var1=>"Guybrush", var2=>"Purcell" );
[download]

  use Text::MicroMason;
  $interpreter = Text::MicroMason->new( -HTMLTemplate );
  $template = "bar <TMPLVAR NAME="var1"> foo <TMPLVAR NAME="var2"> bar
+ BAAAR!";
  $subroutine = $interpreter->compile( $template );
  $output = $subroutine->( var1=>"Guybrush", var2=>"Purcell" );
[download]