[Power Query] [m] Closures

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[Power Query] [m] Closures

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Last edited Oct 13, 2017

Created on Oct 12, 2017

This example visualizes the inner workings of a TypeScript-based function-closure mechanism, showing how parameter lists are programmatically overwritten and restricted. It demonstrates the step-by-step process of copying a function (`fnCopy`) and applying `setParameters` to limit its arguments to a specific range, then wrapping that operation with another `setParameters` call to further constrain the allowed parameter indices to 1–9. The code uses TypeScript’s type system and higher-order functions (like `setParameters`) to manipulate closures at runtime. The rendering approach is textual, highlighting the sequential logic through code snippets, with no graphical or data-driven output beyond the functional transformation.

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