18 lines
431 B
R
18 lines
431 B
R
s <- sapply (1:10,
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function (x) {
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x # force evaluation of promise x
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function () {
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R <- x*x
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# evaluate the language expression "x <- x + 1" in the persistent parent environment
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evalq (x <- x + 1, parent.env(environment()))
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R # return squared value
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}})
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s[[5]]()
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[1] 25 # 5^2
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s[[5]]()
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[1] 36 # now 6^2
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s[[1]]()
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[1] 1 # 1^2
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s[[1]]()
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[1] 4 # now 2^2
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