if(...){...}else{...} is considered a statement rather than an expression. Any expression can be used as a statement, but many statements cannot be used as an expression.

In a list (which is what a hash is initialized with), the list items are expected to be given as expressions, not statements.

The ternary operator is an expression, which is why that works.

A do{...} block allows you to provide a block of statements and wrap it up into an expression:

my %weather = (
   precipitation => do {
      if ($rain == 0) {
         "dry";
      }
      else {
         "wet";
      }
   },
);

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use Moops; class Cow :rw { has name => (default => 'Ermintrude') }; say Cow->new->name

In reply to Re^2: Conditional within Hash definition by tobyink
in thread Conditional within Hash definition by veryan

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