7557542bc2
This PR modifies the `structure` syntax so that parents can be named, like in ```lean structure S extends toParent : P ``` **Breaking change:** The syntax is also modified so that the resultant type comes *before* the `extends` clause, for example `structure S : Prop extends P`. This is necessary to prevent a parsing ambiguity, but also this is the natural place for the resultant type. Implements RFC #7099. Will need followup PRs for cleanup after a stage0 update.
104 lines
2.3 KiB
Text
104 lines
2.3 KiB
Text
/-!
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# Testing named parent projections for `structure`s
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-/
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structure S where
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x : Nat
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structure T where
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y : Nat
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structure U where
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x : Nat
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/-!
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Non-atomic parent projections are not allowed.
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-/
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/-- error: invalid parent projection name 'non.atomic', names must be atomic -/
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#guard_msgs in structure S' extends non.atomic : S
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/-!
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Shadowing other fields is not allowed.
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-/
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/-- error: field 'x' has already been declared -/
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#guard_msgs in structure S' extends x : S
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/-!
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Duplicate parent projections
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-/
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/-- error: field 'toP' has already been declared -/
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#guard_msgs in structure S' extends toP : S, toP : T
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/-!
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Duplicate parent projections because from different namespaces
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-/
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structure NS1.S
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structure NS2.S
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/--
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error: field 'toS' has already been declared, use 'toParent : P' syntax to give a unique name for the parent projection
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-/
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#guard_msgs in structure S' extends NS1.S, NS2.S
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/-!
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Duplicate parent projections, when there are overlapping fields
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-/
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/-- error: field 'toS' has already been declared -/
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#guard_msgs in structure S' extends S, toS : U
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/-- error: field 'toP' has already been declared -/
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#guard_msgs in structure S' extends toP : S, toP : T
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/-!
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Duplicate parent projections because from different namespaces, when there are duplicate fields
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-/
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structure NS1.S' where x : Nat
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structure NS2.S' where x : Nat
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/--
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error: field 'toS'' has already been declared, use 'toParent : P' syntax to give a unique name for the parent projection
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-/
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#guard_msgs in structure S' extends NS1.S', NS2.S'
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/-!
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Field conflicts with projection
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-/
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/-- error: field 'toS' has already been declared as a projection for parent 'S' -/
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#guard_msgs in structure S' extends S where
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toS : Nat
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/-!
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Checking that the projection name is honored.
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-/
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structure S2 extends toTheS : S where
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y : Nat
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/--
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info: structure S2 : Type
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number of parameters: 0
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parents:
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S2.toTheS : S
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fields:
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S.x : Nat
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S2.y : Nat
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constructor:
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S2.mk (toTheS : S) (y : Nat) : S2
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field notation resolution order:
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S2, S
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-/
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#guard_msgs in #print S2
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/-!
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Checking that the projection name is honored.
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-/
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structure S2' extends toTheS : S, toTheU : U where
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y : Nat
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/--
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info: structure S2' : Type
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number of parameters: 0
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parents:
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S2'.toTheS : S
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S2'.toTheU : U
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fields:
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S.x : Nat
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S2'.y : Nat
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constructor:
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S2'.mk (toTheS : S) (y : Nat) : S2'
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field notation resolution order:
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S2', S, U
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-/
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#guard_msgs in #print S2'
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