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The article also says this is valid within the grid: One last thing to note, is that you can call a lambda without naming it. If we hadn’t named the previous f

The article also says this is valid within the grid: One last thing to note, is that you can call a lambda without naming it. If we hadn’t named the previous formula, and just authored it in the grid, we could call it like this: =LAMBDA(x, x+122)(1) Edit: typo

ripley12 6y ago
Yeah, that’s why I added a qualifier. I can’t see that being much use outside of testing/debugging functions, since it would usually be simpler to just write that without the LAMBDA call.
- int_19h 6y ago
  They can also be referenced via the cells. You could argue that cells are themselves named, but those names are really indices into a 2D array, you can have relative references or do offset-based math if needed, and there's indirection (i.e. you can use an arbitrary value as an index to read/write another value). Given all this, an index of a cell containing a lambda is really a lot like a function reference, and can be used in much the same way - passed around etc. So, these are anonymous functions. The more interesting question is whether they're closures - that is, whether a LAMBDA nested in another LAMBDA can reference the latter's parameters, and how it interacts with LET (https://support.microsoft.com/en-us/office/let-function-34842dd8-b92b-4d3f-b325-b8b8f9908999 https://support.microsoft.com/en-us/office/let-function-3484...).
  - ripley12 6y ago
    Huh, are you sure? I don’t think you can (currently) define a lambda in a cell without also calling it in that cell (which means the cell now evaluates to the function’s return value, not a function). The LAMBDA docs: “If you create a LAMBDA function in a cell without also calling it from within the cell, Excel returns a #CALC! error.” https://support.microsoft.com/en-us/office/lambda-function-bd212d27-1cd1-4321-a34a-ccbf254b8b67?ui=en-US&rs=en-CA&ad=CA https://support.microsoft.com/en-us/office/lambda-function-b...
    - int_19h 6y ago
      It will show #CALC! for that cell because, well, it has to show something for the result of the formula - but the formula didn't evaluate to a "displayable" value.
      - ripley12 6y ago
        Yeah that wasn't the best example on my part. But I have tried it and confirmed that calling lambdas defined in another grid cell doesn't work. Specifically: 1) Put =LAMBDA(x, x+1) in A1 2) Try calling =A1(1) from any other cell - it will return #REF! I'm on the Office Insiders beta track and LAMBDA does work otherwise.

ripley12 6y ago

Yeah, that’s why I added a qualifier. I can’t see that being much use outside of testing/debugging functions, since it would usually be simpler to just write that without the LAMBDA call.

int_19h 6y ago
They can also be referenced via the cells. You could argue that cells are themselves named, but those names are really indices into a 2D array, you can have relative references or do offset-based math if needed, and there's indirection (i.e. you can use an arbitrary value as an index to read/write another value). Given all this, an index of a cell containing a lambda is really a lot like a function reference, and can be used in much the same way - passed around etc. So, these are anonymous functions. The more interesting question is whether they're closures - that is, whether a LAMBDA nested in another LAMBDA can reference the latter's parameters, and how it interacts with LET (https://support.microsoft.com/en-us/office/let-function-34842dd8-b92b-4d3f-b325-b8b8f9908999 https://support.microsoft.com/en-us/office/let-function-3484...).
- ripley12 6y ago
  Huh, are you sure? I don’t think you can (currently) define a lambda in a cell without also calling it in that cell (which means the cell now evaluates to the function’s return value, not a function). The LAMBDA docs: “If you create a LAMBDA function in a cell without also calling it from within the cell, Excel returns a #CALC! error.” https://support.microsoft.com/en-us/office/lambda-function-bd212d27-1cd1-4321-a34a-ccbf254b8b67?ui=en-US&rs=en-CA&ad=CA https://support.microsoft.com/en-us/office/lambda-function-b...
  - int_19h 6y ago
    It will show #CALC! for that cell because, well, it has to show something for the result of the formula - but the formula didn't evaluate to a "displayable" value.
    - ripley12 6y ago
      Yeah that wasn't the best example on my part. But I have tried it and confirmed that calling lambdas defined in another grid cell doesn't work. Specifically: 1) Put =LAMBDA(x, x+1) in A1 2) Try calling =A1(1) from any other cell - it will return #REF! I'm on the Office Insiders beta track and LAMBDA does work otherwise.