Thin the blood and prevent clots (if you have a man-made replacement valve). Doctors also prescribe these medicines for mitral stenosis or other valve defects that raise the risk of blood clots. Treat coronary heart disease. Medicines for coronary heart disease can reduce your heartâs workload and relieve symptoms.
undefined is a property of the global object, i.e. it is a variable in global scope. The initial value of undefined is the primitive value undefined. In modern browsers (JavaScript 1.8.5 / Firefox 4+), undefined is a non-configurable, non-writable property per the ECMAScript 5 specification. Even when this is not the case, avoid overriding it.
The dereferencing as a hash is done with the %{ } , and the undefined value is the empty array slice you took with @_[0] (although what you actually want when you retrieve a single element of an array is the $ sigil, like the warnings tell you).he @_ array is only useful inside of subroutines, where it contains the arguments that the subroutine is called with. For an intro to references in Perl, see perldoc perlreftut. For explanations on particular warnings, see perldoc perldiag, or put use diagnostics; in your script to enable verbose warnings.