MFP language variable statement:

Variable statement is used to define one or several variables. It should be always like

variable var1{=expr1}, var2{=expr2}, var3{=expr3}, ..., varN{=exprN}

, where var1, var2, var3, ..., varN are variables' names. N can be any positive integer. And {=expr*} means the initial value assignment can be ignored (with default initial value is NULL). For example, statement

variable a = "hello, world", b, c = a + 7, d=[2,3,[5,8]]

declares four variables whose name are a, b, c, and d and whose initial values are "hello, world", NULL, "hello, world7" and [2, 3, [5, 8]] respectively.