Help with macro/template extrapolating of parameters

[jyapayne]

I think this is exactly what you want, minus the `do:`
    
    
    import macros
    import std/envvars, std/options
    
    type
      EnvType = object
        m_user: Option[string]
        m_icloud_dir: Option[string]
    
    var Env*: EnvType
    
    macro defineEnv*(fieldName, body: untyped): untyped =
      let newName = ident("m_" & fieldName.strVal)
      return quote do:
        proc `fieldName`*(env: var EnvType): string =
          if isNone(env.`newName`):
            result = `body`
            env.`newName` = some result
          else:
            result = env.`newName`.get
    
    define_env user:
      "USER".getEnv
    
    
    define_env icloud_dir: "/Users/" & Env.user & 
"/Library/CloudStorage/Box-Box"
    echo Env.user
    echo Env.icloud_dir
    
    
    Run