In PL/ 1, the state in which a preprocessor variable or entry name is said to be when its value cannot replace the corresponding identifier in source program text. 在pl/1语言中,当预处理程序变量或入口名的值不能替换源程序文本中相应的标识符时的状态。
Design of a Preprocessor Circuit for Variable Bandwidth Analog Signals 一种可变带宽模拟信号预处理电路设计