Terms & Literals

externalConstant

A reference to an externally supplied constant value, prefixed with %. The name may be a keyword identifier, a plain identifier, or a string literal. External constants are resolved by the evaluation environment at runtime.

function

A function call expression consisting of a referential identifier followed by a parenthesized argument list. Resolves to a named function definition in the current or an included library.

invocation

An invocation refers to a named member or function call. It also includes special invocations: $this (current element), $index (current index), and $total (current aggregate total).

literal

A literal is a compile-time constant value. CQL supports Boolean, null, string, integer, long integer, date/time, quantity, and ratio literals.

qualifiedFunction

A function call that appears after a dot operator, using a name drawn from the set of identifiers and function identifiers. Accepts an optional argument list and is used for method-style invocation of fluent functions.

qualifiedInvocation

An invocation that appears after a dot operator on an expression term. Either a member access (referential identifier) or a method call (qualified function). Used for property navigation and fluent function calls.

ratio

A ratio literal consisting of two quantity values separated by a colon. Represents a proportional relationship between two measured quantities, such as 1 'mg' : 2 'mL'.

term

A term is the most fundamental expression unit. It can be an identifier invocation, a literal value, an external constant, a selector expression, or a parenthesized expression.