Porosing new syntax extension to mezze

Mezze Current Syntax.ml

  # =============================================================================
  # Mezze - Current Style
  # =============================================================================
  #
  # - Explicit module-qualified calls
  # - All parameters named
  # - Many let bindings to avoid deep nesting
  # - Must know module/ability names upfront
  # =============================================================================

  ability Show 'a where {
      show: {value: 'a} -> String,
  }

  type User = {name: String, age: Int, email: String}

  impl Show User where {
      show = {value} -> "User($(value.name), $(value.age))",
  }

  # --- Processing: step by step with let bindings ---
  let formatUser: {data: String} -> String = {data} ->
      let trimmed = string::trim {s = data}
      let lower = string::toLower {s = trimmed}
      let parsed = json::parse {s = lower}
      let user = User.fromJson {json = parsed}
      let display = Show.show {value = user}
      "Found: $(display)"

  # --- Or deeply nested (inside-out, hard to follow) ---
  let formatUserNested: {data: String} -> String = {data} ->
      let user = User.fromJson {
          json = json::parse {
              s = string::toLower {
                  s = string::trim {s = data}
              }
          }
      }
      "Found: $(Show.show {value = user})"

  let main = perform Console in
     let result = formatUser {data = "  {\"name\": \"Alice\", \"age\": 30}  "}
     println {msg = result}

Mezze Proposed Syntax.ml

  # =============================================================================
  # Mezze - New Style (Proposed)
  # =============================================================================
  #
  # - Method chaining: data flows left-to-right, top-to-bottom
  # - IDE discovery: type "value." to see available methods
  # - Inlay hints show type at each step of chain
  # - "it" is implicit receiver in impl blocks
  # =============================================================================

  ability Show for 'a where {
      show: {} -> String,
  }

  type User = {name: String, age: Int, email: String}

  impl Show for User where {
      show = {} -> "User($(it.name), $(it.age))",
  }

  # Adding methods directly to User (anonymous impl)
  impl User where {
      isAdult = {} -> it.age >= 18,
      domain = {} -> it.email.split {sep = "@"}.last {},
  }

  let formatUser: {data: String} -> String = {data} ->
      data
          .trim {}
          .toLower {}
          .parseJson {}
          .toUser {}
          .show {}
          .prepend {s = "Found: "}

  let main = perform Console in
     let result = formatUser {data = "  {\"name\": \"Alice\", \"age\": 30}  "}
     println {msg = result}

  # --- Processing: method chain, reads naturally ---
  #
  # IDE inlay hints:
  #   data.trim {}        : String
  #       .toLower {}     : String
  #       .parseJson {}   : Json
  #       .toUser {}      : User
  #       .show {}        : String
  #       .prepend {...}  : String
  #