isGlobalSymbol -- whether a global symbol with a given name exists

• Usage:

  isGlobalSymbol s

• Inputs:
  • s, a string
• Outputs:
  • a Boolean value, whether a global symbol with the name contained in the string
  • s
  • has been defined

i1 : isGlobalSymbol "res"

o1 = true

i2 : isGlobalSymbol "resres"

o2 = false