NAME

@typeof - Determine the type of an object at runtime

SYNOPSIS

@typeof {INPUT}

DESCRIPTION

The @typeof operator is used to determine the type of a pointer at runtime. The directive is expanded to the result described below.

The result of the @typeof directive will be either:

The class name of the object if the input is a valid pointer to an object.
An empty string otherwise.

EXAMPLE

echo @typeof &@object
echo @typeof @pointer
echo @typeof "abc" # Blank line

if [[ @typeof &@object == "ExpectedClass" ]]; then
	# '@object' is an instance of 'ExpectedClass'
fi

NOTES

EXPANSION

The @typeof directive expands to the result described above. This result is then interpreted according to the shell context in which the directive is used. For example, if the directive is used in a context where a command is expected, the result will be treated as a command. If it is used in a context where an argument is expected, the result will be treated as an argument.

echo @typeof @ptr # Passes the result as an argument to 'echo'
var=@typeof @ptr  # This assigns the result to a variable
@typeof @ptr      # Watch out! This attempts to run the result as a command; you'll probably see "command not found."

INPUT

The input to the @typeof directive is that which is being inspected. The input can be any rvalue at all, but should be a pointer to an object.

An easy mistake to make, for example, would be to pass an object directly instead of its address – this would implicitly call the object’s toPrimitive method, and attempt to find the “type of” that method’s output.