Add tests for E-expressions using simple system macros. #100
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| (toplevel ('#$:make_string' "a" b )) | ||
| (toplevel ('#$:make_string' a "b")) | ||
| (produces "ab")) | ||
| // null.string and null.symbol act like "" |
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Interesting; does $0 also behave this way? I think I expected null arguments to be an error.
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Great question, I tend to forget about $0. Heck, we also have absent symbols to deal with.
I cut amazon-ion/ion-docs#324 to deal with that later.
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I spec'd nulls to act like "" because their presence doesn't seem problematic enough to treat exceptionally. This way all (known) symbol and string values are accepted without error.
(The cases you call out are arguably encoding defects, so I think they deserve more global handling.)
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Adding a bit more detail on my thought process: the typed signature of this macro would be (text::v*) and I think its preferable for it to succeed given any text value. So that would include null.string and null.symbol for sure, and $0 is technically a valid non-null symbol. All of the above have no text, so I conclude that its reasonable to accept and ignore them (which happens to be indistinguishable from treating them as "").
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@zslayton I cut amazon-ion/ion-docs#327 -- and there's also amazon-ion/ion-docs#324 -- if those don't cover your concerns well, please comment there. |
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