---
source: tests/snapshot/main.rs
expression: out
---
{
  field
    | doc m%%"
    Contract to enforce the value is a string that represents a boolean literal. Additionally casts "True" to "true"
    and "False" to "false". This shouldn't interpolate: %{null}
    
    For example:
    ```nickel
      ("True" | BoolLiteral) =>
        "true"
      ("hello" | BoolLiteral) =>
        error
      (true | BoolLiteral) =>
        error
    ```
    "%%
    = 1,
}