functional programming - is any JavaScript statement an expression? -

i know functional languages lisp don't have statements. there expression. javascript functional language. came conclusion every javascript statement expression. thought came mind when playing chrome's console. every statement entered there evaluated , console returns undefined if expression doesn't return value.

i'd no, can't use statement expression expected:

// syntaxerror: unexpected token var var = var b; 

// syntaxerror: unexpected token if var c = if (true) {}; 

the undefined shown in chrome's console due use of eval() (or native/internal equivalent), evaluates code:

var = eval('var b;'); console.log(a); // undefined 

the undefined isn't result of var b;, because eval() still has return value -- whether evaluated code supplied or not.