protect -- protect a symbol

Synopsis

• Usage:

  protect s

• Inputs:
  • s, a symbol
• Outputs:
  • s, a symbol
• Consequences:

  • the symbol s is protected from having its value changed

Description

There is no function for unprotecting symbols.

i1 : mutable symbol s

o1 = true

i2 : s = 5

o2 = 5

i3 : s

o3 = 5

i4 : protect symbol s

o4 = s

o4 : Symbol

i5 : mutable symbol s

o5 = false

i6 : try s = 7

i7 : s

o7 = 5

See also

• mutable -- whether something may be modified
• try -- catch an error