syntax changes (srfi-107/108/109)
Per Bothner
(29 Dec 2012 21:43 UTC)
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Re: syntax changes (srfi-107/108/109) John Cowan (30 Dec 2012 03:22 UTC)
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Re: syntax changes (srfi-107/108/109)
John Cowan
(30 Dec 2012 03:37 UTC)
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Re: syntax changes (srfi-107/108/109)
Per Bothner
(30 Dec 2012 04:45 UTC)
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Re: syntax changes (srfi-107/108/109)
John Cowan
(31 Dec 2012 07:37 UTC)
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Re: syntax changes (srfi-107/108/109)
Per Bothner
(31 Dec 2012 08:42 UTC)
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Re: syntax changes (srfi-107/108/109) John Cowan 30 Dec 2012 03:22 UTC
Per Bothner scripsit: > There is a seeming ambiguity, since in Scheme the character '&' > is a valid symbol character. However, a symbol followed > immediately by either '{' or '[' is not defined by standard > Scheme, so this is a conflict-free extension. Unfortunately, &condition[car '(a b c)] is perfectly well-defined R6RS lexical syntax, where [] means the same as () and symbols beginning with ampersands are actually standard for names of condition types. I don't say it should be that way, but it is. > &{Hello world!} > &{Hello &[name]!} +1 > §ion{News as of &(current-date)} This being, I presume, shorthand for §ion{News as of &[(current-date)]}. > + Kawa has this syntax for a vector constructor: > [e1 e2 ... en] > This is the same as `#(,e1 ,e2 ... ,en), which is the same as > (vector e1 e2 .. en) except producing an immutable vector. More to the point, the last is code, whereas the first two are lexical syntax and therefore work in data. I think it's important to always keep the data applications firmly in mind. -- I marvel at the creature: so secret and John Cowan so sly as he is, to come sporting in the pool xxxxxx@ccil.org before our very window. Does he think that http://www.ccil.org/~cowan Men sleep without watch all night?