36c7d46c34
See #1480 @semorrison We can now use the following commands to trace the rewrite tactic ```lean set_option trace.rewrite true set_option trace.kabstract true ``` When these options are used, Lean will pretty print the subterm selected by the rewrite tactic. That is, the subterm that will be rewritten. This option may help you diagnose what is going on.
8 lines
157 B
Text
8 lines
157 B
Text
set_option trace.rewrite true
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set_option trace.kabstract true
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example (f : nat → nat) (a b : nat) (h : f a = a) : f (f a) = a :=
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begin
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rw h,
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rw h
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end
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