AQLCollectionExpression

struct AQLCollectionExpression

Overview

Collection operations allow filtering, transformation, and querying of collections in AQL expressions. These operations follow OCL semantics.

Supported Operations

Filtering

• select(iterator | condition) - Filter elements matching condition

• reject(iterator | condition) - Filter elements not matching condition

Transformation

• collect(iterator | expression) - Transform each element

Querying

• any(iterator | condition) - True if any element matches

• forAll(iterator | condition) - True if all elements match

• exists(iterator | condition) - True if any element matches (alias for any)

Properties

• size() - Number of elements

• isEmpty() - True if collection is empty

• notEmpty() - True if collection is not empty

• first() - First element or null

• last() - Last element or null

Element Lookup

• indexOf(element) - 0-based index of first matching element, or -1 if not found

Example Usage

// Filter: persons->select(p | p.age > 18)
let adultsExpr = AQLCollectionExpression(
    source: personsExpr,
    operation: .select,
    iterator: "p",
    body: ageComparisonExpr
)

// Transform: persons->collect(p | p.name)
let namesExpr = AQLCollectionExpression(
    source: personsExpr,
    operation: .collect,
    iterator: "p",
    body: nameNavigationExpr
)

// Query: persons->size()
let sizeExpr = AQLCollectionExpression(
    source: personsExpr,
    operation: .size
)