txt: ## prepost.md
  class X::Phaser::PrePost
  
  Error due to a false return value of a PRE/POST phaser
  
  ```raku
  class X::Phaser::PrePost is Exception { }
  
  ```
  
  Thrown when the condition inside a `PRE` or `POST` phaser evaluate to a false value.
  
  For example
  
  ```raku
  sub f($x) { PRE { $x ~~ Int } };
  f "foo";
  CATCH { default { put .^name, ': ', .Str } };
  # OUTPUT: X::Phaser::PrePost: Precondition '{ $x ~~ Int }' failed«␤»
  ```
  
  # [Methods](#class_X::Phaser::PrePost "go to top of document")[§](#Methods "direct link")
  
  ## [method phaser](#class_X::Phaser::PrePost "go to top of document")[§](#method_phaser "direct link")
  
  ```raku
  method phaser(--> Str:D)
  ```
  
  Returns the name of the failed phaser, `"PRE"` or `"POST"`.
  
  ## [method condition](#class_X::Phaser::PrePost "go to top of document")[§](#method_condition "direct link")
  
  ```raku
  method condition(--> Str:D)
  ```
  
  Returns the part of the source code that describes the phaser condition.
  