def Lean.Parser.Tactic.unknown : Parser

def Lean.Parser.Tactic.nestedTactic : Parser

def Lean.Parser.Tactic.matchRhs : Parser

def Lean.Parser.Tactic.matchAlts : Parser

def Lean.Parser.Tactic.match : Parser

match performs case analysis on one or more expressions. See Induction and Recursion. The syntax for the match tactic is the same as term-mode match, except that the match arms are tactics instead of expressions.

example (n : Nat) : n = n := by
  match n with
  | 0 => rfl
  | i+1 => simp

def Lean.Parser.Tactic.introMatch : Parser

The tactic

intro
| pat1 => tac1
| pat2 => tac2

is the same as:

intro x
match x with
| pat1 => tac1
| pat2 => tac2

That is, intro can be followed by match arms and it introduces the values while doing a pattern match. This is equivalent to fun with match arms in term mode.