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Indentation errors with light syntax under "module"
f#

Everything below uses the #light syntax, with indentation as shown.

The following code is fine:

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module test
    let x = 1.0  // this is OK

The following gets an error on the last line "error in the return expression for this 'let'. Possible incorrect indentation."

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module test
    let x = 1.0  // this is OK
    let y = 2.0  // indentation error if this is the last line

The following gets an error on the last line, no error on the line above which is got the error above:

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module test
    let x = 1.0  // this is OK
    let y = 2.0  // indentation error if this is the last line
    let z = 3.0  // indentation error if this is the last line

This one gets two errors:

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module test
    let x = 1.0  // indentation error
        let y = 2.0  // indentation error on this line too

This, using no indentation, gets no errors.

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module test
let x = 1.0  // OK
let y = 2.0  // OK too

Are there some rules for maintaining readability (i.e. using reasonable indentation) while avoiding these errors within modules?

.

You can just insert an "open System" after your "module test" line. I find it's a good workaround too.

By on 2/8/2009 10:26 AM ()

The language syntax here is a little nuts.

If you put an '=' after 'module test' then your original first errors will go away (entities must be indented). Then they become entities named e.g. 'Filename.test.x' - you are using the implicit module. Without the '=', you get rid of the implicit module, and the entire file goes in a module named 'test' (e.g. 'test.x'), and you don't indent (apparently indenting makes it a 'do' expression, which is incomplete if it only contains 'let's as there's no body).

I need to write a blog to explain all this in more detail. I'll also file a bug for better error diagnostics.

By on 2/3/2009 1:40 PM ()

It works! Thanks Brian.

By on 2/3/2009 2:14 PM ()

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