RowExpression.From as JSON

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RowExpression.From as JSON

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Last edited Mar 6, 2018

Created on Mar 7, 2018

This example demonstrates a Power Query M script that converts a `RowExpression` result into JSON text, revealing the internal structure of row and function type metadata. It shows how the script recursively normalizes values—turning tables, records, and lists into JSON-compatible forms while replacing functions and type values with descriptive strings. The code relies on the M standard library functions `Json.FromValue`, `Text.FromBinary`, and `Type.Is`/`Type.IsNullable` to map primitive and complex types to their JSON representations. It also uses table and record manipulation functions like `Table.TransformColumns`, `Record.FromList`, and `Type.FunctionParameters` to expose parameter details, required flags, and nullable status. The final output is a serialized JSON string generated from the evaluated expression.

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