35 lines
794 B
Scheme
35 lines
794 B
Scheme
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(load "util.scm")
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(display "\nex-5.31\n")
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; 1. save and restore env around operator
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; 2. save and restore env around each operand (except last)
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; 3. save and restore argl around each operand
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; 4. save and restore proc around operand sequence
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; (f 'x 'y)
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; 1-4 are superfluous
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; ((f) 'x 'y)
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; 1-4 are superfluous
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; no need to save env because compound-apply without args does
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; not change env
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; (f (g 'x) y)
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; 1 is superfluous
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; we need 2 because (g 'x) changes the env for y
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; we need 3 because (g 'x) changes argl
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; we need 4 because (g 'x) changes proc
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; (f (g 'x) 'y) ; 1 is superfluous
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; 1-2 are superfluous
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; (g 'x) changes the env but we don't need it later (better save it anyway)
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; 3-4 are still needed
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(display "[answered]\n")
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(display "\nex-5.32\n")
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(display "\nex-5.33\n")
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