RowExpression.From

Syntax

RowExpression.From(function as function) as record

About

Returns the AST for the body of function, normalized into a row expression:

  • The function must be a 1-argument lambda.
  • All references to the function parameter are replaced with RowExpression.Row.
  • All references to columns are replaced with RowExpression.Column(columnName).
  • The AST will be simplified to contain only nodes of the kinds:
    • Constant
    • Invocation
    • Unary
    • Binary
    • If
    • FieldAccess
    • NotImplemented

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

Example 1

Returns the AST for the body of the function each [CustomerID] = "ALFKI"

RowExpression.From(each [CustomerName] = "ALFKI")  

[ Kind = "Binary", Operator = "Equals", Left = RowExpression.Column("CustomerName"), Right = [ Kind = "Constant", Value = "ALFKI" ] ]