Function: _def_strictargs
Class: default
Section: default
C-Name: sd_strictargs
Prototype:
Help:
Doc: this toggle is either 1 (on) or 0 (off). If on, all arguments to \emph{new}
 user functions are mandatory unless the function supplies an explicit default
 value.
 Otherwise arguments have the default value $0$.

 In this example,
 \bprog
   fun(a,b=2)=a+b
 @eprog
 \kbd{a} is mandatory, while \kbd{b} is optional. If \kbd{strictargs} is on:
 \bprog
 ? fun()
  ***   at top-level: fun()
  ***                 ^-----
  ***   in function fun: a,b=2
  ***                    ^-----
  ***   missing mandatory argument 'a' in user function.
 @eprog
 This applies to functions defined while \kbd{strictargs} is on. Changing \kbd{strictargs}
 does not affect the behavior of previously defined functions.

 The default value is \kbd{0}.
