c292ae2e0e
This PR makes the arity reduction pass in the new code generator match the old one when it comes to the behavior of decls with no used parameters. This is important, because otherwise we might create a top-level decl with no params that contains unreachable code, which would get evaluated unconditionally during initialization. This actually happens when initializing Init.Core built with the new code generator.
29 lines
851 B
Text
29 lines
851 B
Text
import Lean
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/-- `erased α` is the same as `α`, except that the elements
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of `erased α` are erased in the VM in the same way as types
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and proofs. This can be used to track data without storing it
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literally. -/
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def Erased (α : Sort u) : Sort max 1 u :=
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Σ's : α → Prop, ∃ a, (fun b => a = b) = s
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namespace Erased
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/-- Erase a value. -/
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@[inline]
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def mk {α} (a : α) : Erased α :=
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⟨fun b => a = b, a, rfl⟩
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open Lean.Compiler
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set_option pp.explicit true
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set_option pp.funBinderTypes true
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set_option pp.letVarTypes true
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set_option trace.Compiler.result true
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/--
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info: [Compiler.result] size: 1
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def Erased.mk (α : lcErased) (a : lcAny) : PSigma lcErased lcErased :=
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let _x.1 : PSigma lcErased lcErased := PSigma.mk lcErased ◾ ◾ ◾;
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return _x.1
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-/
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#guard_msgs in
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run_meta Lean.Compiler.compile #[``Erased.mk]
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