[plt-scheme] If expressions in Embedded PLT Scheme

2008/10/8 Samuel Rebelsky <rebelsky at grinnell.edu>
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> I am embedding MzScheme/PLT Scheme in a program.
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> In MzScheme (v372 is the one I had been using), it was permissible to write if expressions without an alternate, as in
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>  (if (> x 1) (display x))
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> When I embed the new PLT Scheme (v401, I think), for the same expression, I get an error message that it 'must have an "else" expression'.
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> R6RS seems to suggest that the no-alternate form is still valid
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>  http://www.r6rs.org/final/html/r6rs/r6rs-Z-H-14.html#node_sec_11.4.3
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> Is there a way to turn off the "require alternate" behavior in embedded PLT Scheme?

It's generally recommended to use 'when' instead in this case.

    Henk