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ItemExpression.From

Returnerer det abstrakte syntakstræ (AST) for en funktions brødtekst.

Syntax​

ItemExpression.From(
    function as function
) as record

Remarks​

Returns the abstract syntax tree (AST) for the body of function, normalized into an item expression:

  • The function must be a 1-argument lambda.
  • All references to the function parameter are replaced with ItemExpression.Item.
  • The AST will be simplified to contain only nodes of the kinds:
    • Constant
    • Invocation
    • Unary
    • Binary
    • If
    • FieldAccess

An error is raised if an item expression AST cannot be returned for the body of function.

This function is identical to RowExpression.From.

Examples​

Example #1​

Returns the AST for the body of the function each _ <> null.

ItemExpression.From(each _ <> null)

Result:

[
    Kind = "Binary",
    Operator = "NotEquals",
    Left = ItemExpression.Item,
    Right =
    [
        Kind = "Constant",
        Value = null
    ]
]

Category​

Table.Table construction