guard (redirected from on guard)

guard

1. Brit the official in charge of a train

2. Sport an article of light tough material worn to protect any of various parts of the body

3. Basketball

a. the position of the two players in a team who play furthest from the basket

b. a player in this position

4. the posture of defence or readiness in fencing, boxing, cricket, etc.

5. take guard Cricket (of a batsman) to choose a position in front of the wicket to receive the bowling, esp by requesting the umpire to indicate his position relative to the stumps

6. give guard Cricket (of an umpire) to indicate such a position to a batsman

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(programming)

guard - 1. In functional programming, a Boolean expression attached to a function definition specifying when (for what arguments) that definition is appropriate. 2. In (parallel) logic programming, a Boolean expression which is used to select a clause from several alternative matching clauses. See Guarded Horn Clauses. 3. In parallel languages, a Boolean expression which specifies when an message may be sent or received.