Gas and Chemical Exposure. NOTE: This is the Consumer Version. Symptoms depend on which gas or chemical is inhaled and how deeply and for how long it was inhaled. Symptoms may include irritation of the eyes or nose, cough, blood in the sputum, and shortness of breath. Chest x-rays, computed tomography, and breathing tests are used to determine how much lung damage has occurred.
Scope refers to the visibility of variables and methods in one part of a program to another part of that program. The importance and meaning of scope varies between languages, but there are two general scope concepts many languages have in common: local and global scope.
There are names for functions, names for variables, and so on. When a name appears, it either defines the meaning of the name or refers to a definition elsewhere. The scope of a definition is the part of the program over which the definition holds. Every programming language has its own rules for determining scope. For example, in the following bit of Python, the second line refers to the x that was defined on the first line.