25 lines
No EOL
433 B
Scheme
25 lines
No EOL
433 B
Scheme
#lang sicp
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(define (make-frame origin edge1 edge2)
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(list origin edge1 edge2))
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; selectors for the first:
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(define (origin-frame f)
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(car f))
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(define (edge1-frame f)
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(cadr f))
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(define (edge2-frame f)
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(caddr f))
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(define (make-frame origin edge1 edge2)
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(cons origin (cons edge1 edge2)))
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; selectors for the second:
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(define (origin-frame f)
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(car f))
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(define (edge1-frame f)
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(cadr f))
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(define (edge2-frame f)
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(cddr f)) |