conditional-expressions

I was toying around with java, and I noticed something. It can be best shown here: boolean boo = true; Object object1 = boo ? new Integer(1) : new Double(2.0); Object object2; if (boo) object2 = new Integer(1); else object2 = new Double(2.0); System.out.println(object1); System.out.println(object2); I would expect the two to be the same, but this is what gets printed: 1.0 1 Does anyone have a good explanation for this? A ternary must return the same type for both conditions, so your first result ( Integer ) is promoted to a double to match 2.0 . See also, Object object1 = boo ? new Integer(1)

Noticed a line in our codebase today which I thought surely would have failed the build with syntax error, but tests were passing so apparently it was actually valid python (in both 2.x and 3). Whitespace is sometimes not required in the conditional expression: >>> 1if True else 0 1 It doesn't work if the LHS is a variable: >>> x = 1 >>> xif True else 0 File "<stdin>", line 1 xif True else 0 ^ SyntaxError: invalid syntax But it does seem to still work with other types of literals: >>> {'hello'}if False else 'potato' 'potato' What's going on here, is it intentionally part of the grammar for

Just for curiosity/convenience: C# provides two cool conditional expression features I know of: string trimmed = (input == null) ? null : input.Trim(); and string trimmed = (input ?? "").Trim(); I miss another such expression for a situation I face very often: If the input reference is null, then the output should be null. Otherwise, the output should be the outcome of accessing a method or property of the input object. I have done exactly that in my first example, but (input == null) ? null : input.Trim() is quite verbose and unreadable. Is there another conditional expression for this case,