69b058dc82
This PR implements iteration over ranges for `Fin` and `Char`. To this end, we introduce machinery for pulling back lawfulness of `UpwardEnumerable` along an injective map and study the function `Char.ordinal : Char -> Fin Char.numCodePoints`.
29 lines
492 B
Text
29 lines
492 B
Text
module
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def s₁ : String := Id.run do
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let mut ans := ""
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for c in 'a'...='z' do
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ans := ans.push c
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return ans
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/-- info: "abcdefghijklmnopqrstuvwxyz" -/
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#guard_msgs in
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#eval s₁
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def s₂ : String := Id.run do
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let mut ans := ""
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for c in 'a'...'z' do
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ans := ans.push c
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return ans
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/-- info: "abcdefghijklmnopqrstuvwxy" -/
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#guard_msgs in
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#eval s₂
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/-- info: 122 -/
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#guard_msgs in
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#eval (*...'z').size
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/-- info: 1112064 -/
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#guard_msgs in
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#eval (*...* : Std.Rii Char).size
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