deal with *, /, and %

deal with *, / and % calls primary()

width of screen in pixels

return link n "hops" before or after p if ok, ERROR_PTR if not */

calculate area of a rectangle; throw a Bad_area exception in case of a bad argument

calculate area of a rectangle; return -1 to indicate a bad argument

print lists at higher levels

assume we have seen "let" or "const" handle: name = expression declare a variable called "name" with the initial value "expression"

assume we have seen "let" or "const" handle: name = expression declare a variable called "name" with the initial value "expression"

assume we have seen "let" or "const" handle: name = expression declare a variable called "name" with the initial value "expression"

assume we have seen "let" or "const" handle: name = expression declare a variable called "name" with the initial value "expression"

number of elements in a column

remove p from lst; return a pointer to the link after p*/

remove p from lst; return a pointer to the link after p*/

Helper function to show an error message

one unit of c2 is worth how many units of c1?

deal with + and -

deal with + and -

deal with + and -

deal with + and -

deal with + and -

deal with + and -

deal with + and -

deal with + and -

deal with + and -

deal with + and -

deal with + and -

call-by-value (give the function a copy of the value passed)

find s in list; return 0 for "not found"

find s in list; return 0 for "not found"

find s in list; return 0 for "not found"

return name of sender of Message, if any, otherwise ""

returns the rest of the first line in m that starts with s

returns the rest of the first line in m that starts with s

returns the rest of the first line in m that starts with s

return the subject of the Message, if any, otherwise ""

return the subject of the Message, if any, otherwise ""

find substring x in string s, return pointer to first element of x in s

find substring x in string s, return pointer to first element of x in s