-- in.cue --
import "regexp"

// Issue #655
// When evaluating a value into a struct, and then back into a value, the
// evaluation mode flips from Partial to AllArcs to Back. This is typically
// not an issue, but if a referred field is within a struct generated by a
// builtin, effectively the entire struct needs to be evaluated and special care
// should be taking to not evaluate too early.
builtinCyclePerm0: {
    X: "example.com"

    Y: {
        #components: regexp.FindNamedSubmatch(#"^(?P<host>[[:alnum:].]+)$"#, X)
        host: #components.host
    }

    X: Y.host
}

builtinCyclePerm1: {
    X: Y.host

    Y: {
        #components: regexp.FindNamedSubmatch(#"^(?P<host>[[:alnum:].]+)$"#, X)
        host: #components.host
    }

    X: "example.com"
}

builtinCyclePerm2: {
    Y: {
        #components: regexp.FindNamedSubmatch(#"^(?P<host>[[:alnum:].]+)$"#, X)
        host: #components.host
    }

    X: Y.host
    X: "example.com"
}

builtinCyclePerm3: {
    Y: {
        #components: regexp.FindNamedSubmatch(#"^(?P<host>[[:alnum:].]+)$"#, X)
        host: #components.host
    }

    X: "example.com"
    X: Y.host
}

builtinCyclePerm4: {
    X: "example.com"
    X: Y.host

    Y: {
        #components: regexp.FindNamedSubmatch(#"^(?P<host>[[:alnum:].]+)$"#, X)
        host: #components.host
    }
}

builtinCyclePerm5: {
    X: Y.host
    X: "example.com"

    Y: {
        #components: regexp.FindNamedSubmatch(#"^(?P<host>[[:alnum:].]+)$"#, X)
        host: #components.host
    }
}
-- out/eval --
(struct){
  builtinCyclePerm0: (struct){
    X: (string){ "example.com" }
    Y: (struct){
      #components: (#struct){
        host: (string){ "example.com" }
      }
      host: (string){ "example.com" }
    }
  }
  builtinCyclePerm1: (struct){
    X: (string){ "example.com" }
    Y: (struct){
      #components: (#struct){
        host: (string){ "example.com" }
      }
      host: (string){ "example.com" }
    }
  }
  builtinCyclePerm2: (struct){
    Y: (struct){
      #components: (#struct){
        host: (string){ "example.com" }
      }
      host: (string){ "example.com" }
    }
    X: (string){ "example.com" }
  }
  builtinCyclePerm3: (struct){
    Y: (struct){
      #components: (#struct){
        host: (string){ "example.com" }
      }
      host: (string){ "example.com" }
    }
    X: (string){ "example.com" }
  }
  builtinCyclePerm4: (struct){
    X: (string){ "example.com" }
    Y: (struct){
      #components: (#struct){
        host: (string){ "example.com" }
      }
      host: (string){ "example.com" }
    }
  }
  builtinCyclePerm5: (struct){
    X: (string){ "example.com" }
    Y: (struct){
      #components: (#struct){
        host: (string){ "example.com" }
      }
      host: (string){ "example.com" }
    }
  }
}
-- out/compile --
--- in.cue
{
  builtinCyclePerm0: {
    X: "example.com"
    Y: {
      #components: 〈import;regexp〉.FindNamedSubmatch("^(?P<host>[[:alnum:].]+)$", 〈1;X〉)
      host: 〈0;#components〉.host
    }
    X: 〈0;Y〉.host
  }
  builtinCyclePerm1: {
    X: 〈0;Y〉.host
    Y: {
      #components: 〈import;regexp〉.FindNamedSubmatch("^(?P<host>[[:alnum:].]+)$", 〈1;X〉)
      host: 〈0;#components〉.host
    }
    X: "example.com"
  }
  builtinCyclePerm2: {
    Y: {
      #components: 〈import;regexp〉.FindNamedSubmatch("^(?P<host>[[:alnum:].]+)$", 〈1;X〉)
      host: 〈0;#components〉.host
    }
    X: 〈0;Y〉.host
    X: "example.com"
  }
  builtinCyclePerm3: {
    Y: {
      #components: 〈import;regexp〉.FindNamedSubmatch("^(?P<host>[[:alnum:].]+)$", 〈1;X〉)
      host: 〈0;#components〉.host
    }
    X: "example.com"
    X: 〈0;Y〉.host
  }
  builtinCyclePerm4: {
    X: "example.com"
    X: 〈0;Y〉.host
    Y: {
      #components: 〈import;regexp〉.FindNamedSubmatch("^(?P<host>[[:alnum:].]+)$", 〈1;X〉)
      host: 〈0;#components〉.host
    }
  }
  builtinCyclePerm5: {
    X: 〈0;Y〉.host
    X: "example.com"
    Y: {
      #components: 〈import;regexp〉.FindNamedSubmatch("^(?P<host>[[:alnum:].]+)$", 〈1;X〉)
      host: 〈0;#components〉.host
    }
  }
}