This works for me:
$ crystal eval --time --progress --error-trace 'h=Hash{"one" => 1, "two" => Hash{"foo" => 3}}; printf %[debug: >#{h}< >%s< >%s< >%s<\n], h["one"], h["two"], h["two"];'
debug: >{"one" => 1, "two" => {"foo" => 3}}< >1< >{"foo" => 3}< >{"foo" => 3}<
Execute: 00:00:00.012389834
But this fails:
$ crystal eval --time --progress --error-trace 'h=Hash{"one" => 1, "two" => Hash{"foo" => 3}}; printf %[debug: >#{h}< >%s< >%s< >%s<\n], h["one"], h["two"], h["two"]["foo"];'
error in line 1 (main)
Error: undefined method '[]' for Int32 (compile-time type is (Hash(String, Int32) | Int32))
What is the correct syntax to access the nested value of key "foo"?
In Perl this would be $h{two}{foo}.
After some playing I got this to work:
$ crystal eval --time --progress --error-trace 'h=Hash{"one" => 1, "two" => Hash{"foo" => 3}}; printf %[debug: >#{h}< >%s< >%s< >%s<\n], h["one"], h["two"], h["two"].as(Hash)["foo"];'
debug: >{"one" => 1, "two" => {"foo" => 3}}< >1< >{"foo" => 3}< >3<
Execute: 00:00:00.010882643
But it looks way less compact and efficient syntax like Perl. Is there a better way?