v0.18.4

Bug fixes

• Properly handle semantically anonymous functions (#1666) (368fda0)
• Support optional parameters in d.ts generation (#1665) (b24925c)
• Reject identifier or keyword immediately following a numeric literal (#1662) (7a46aa9)
• Emit a diagnostic when an expression refers to a static element (#1661) (4dc6567)
• Substitute type arguments in 'new' only if prototypes match (#1660) (5981995)
• Fill correct view region in crypto.getRandomValues (#1659) (cc37cc4)

Other

• Add missing tetsts for Array#slice (#1655) (eb36166)