FuncIf

FuncIf[ cond, a, b ] returns a if a condition is true and b if it is false.

Usages

`FuncIf[ cond, a, b ]`

FuncIf[ cond, a, b ] is the expression form of If ... Else ... End: it returns a if cond is True, and b if cond is False. Only the chosen expression is executed, so the other one may even be invalid.

Example	in	out
The condition is true.	`FuncIf[ 5 >> 3, a, b ]`	`a`
The condition is false.	`FuncIf[ 3 >> 5, a, b ]`	`b`
Choose a text.	n := 4 r := FuncIf[Mod[n, 2] == 0, Text[`even`], Text[`odd`]]	r = Text[`even`]
`L[[2]]` does not exist, but it is not executed.	`L := {7} r := FuncIf[Length[L] == 1, 0, L[[2]]]`	`r = 0`

Details

Undecided condition: if cond cannot be decided, FuncIf is left unevaluated: FuncIf[ x >> 3, a, b ] stays FuncIf[x >> 3, a, b]. Use Strict to choose b in that case: FuncIf[ Strict[x >> 3], a, b ] gives b.

Warning

Use comparisons that are evaluated directly, such as ==, >>, <<, >==, <== and <<>>. With >, <, >=, <= or <>, the condition is not evaluated and FuncIf is left unevaluated: FuncIf[ 3 > 5, a, b ] stays FuncIf[3 > 5, a, b].

See also: If, Strict, Greater, EqualsEval