0aacccd8c9
`{s with ...}` is now `{..., ..s}`, which more clearly expresses that the
result type is not necessarily equal to the type of `s` (in absence of an
expected type and a structure name, we still default to the type of `s`).
Multiple fallback sources can be given: `{..., ..s, ..t}` will fall back to
searching a field in `s`, then in `t`. The last component can also be `..`,
which will replace any missing fields with a placeholder.
The old notation will be removed in the future.
46 lines
1.5 KiB
Text
46 lines
1.5 KiB
Text
/-
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Copyright (c) 2016 Microsoft Corporation. All rights reserved.
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Released under Apache 2.0 license as described in the file LICENSE.
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Authors: Leonardo de Moura
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-/
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prelude
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import init.meta.expr
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universe u
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/-- Quoted expressions. They can be converted into expressions by using a tactic. -/
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@[reducible] meta def pexpr := expr ff
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protected meta constant pexpr.of_expr : expr → pexpr
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meta constant pexpr.is_placeholder : pexpr → bool
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meta constant pexpr.mk_placeholder : pexpr
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meta constant pexpr.mk_field_macro : pexpr → name → pexpr
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meta constant pexpr.mk_explicit : pexpr → pexpr
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/-- Choice macros are used to implement overloading. -/
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meta constant pexpr.is_choice_macro : pexpr → bool
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/-- Information about unelaborated structure instance expressions. -/
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meta structure structure_instance_info :=
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(struct : option name := none)
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(field_names : list name)
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(field_values : list pexpr)
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(sources : list pexpr := [])
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/-- Create a structure instance expression. -/
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meta constant pexpr.mk_structure_instance : structure_instance_info → pexpr
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meta constant pexpr.get_structure_instance_info : pexpr → option structure_instance_info
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meta class has_to_pexpr (α : Sort u) :=
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(to_pexpr : α → pexpr)
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meta def to_pexpr {α : Sort u} [has_to_pexpr α] : α → pexpr :=
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has_to_pexpr.to_pexpr
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meta instance : has_to_pexpr pexpr :=
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⟨id⟩
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meta instance : has_to_pexpr expr :=
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⟨pexpr.of_expr⟩
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meta instance (α : Sort u) (a : α) : has_to_pexpr (reflected a) :=
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⟨pexpr.of_expr ∘ reflected.to_expr⟩
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