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path: root/dhall/src/error/text/FieldCollision.txt
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Explanation: You can combine records if they don't share any fields in common,
like this:


    ┌───────────────────────────────────────────┐
    │ { foo = 1, bar = "ABC" } ∧ { baz = True } │
    └───────────────────────────────────────────┘


    ┌────────────────────────────────────────┐
    │ λ(r : { baz : Bool}) → { foo = 1 } ∧ r │
    └────────────────────────────────────────┘


... but you cannot merge two records that share the same field

For example, the following expression is $_NOT valid:


    ┌───────────────────────────────────────────┐
    │ { foo = 1, bar = "ABC" } ∧ { foo = True } │  Invalid: Colliding ❰foo❱ fields
    └───────────────────────────────────────────┘


You combined two records that share the following field:

↳ $txt0

... which is not allowed

Some common reasons why you might get this error:

● You tried to use ❰∧❱ to update a field's value, like this:


    ┌────────────────────────────────────────┐
    │ { foo = 1, bar = "ABC" } ∧ { foo = 2 } │
    └────────────────────────────────────────┘
                                   ⇧
                                   Invalid attempt to update ❰foo❱'s value to ❰2❱

  Field updates are intentionally not allowed as the Dhall language discourages
  patch-oriented programming