Function: _parforprime_init
Class: gp2c_internal
Help: Initializes parameters for parforprime.
Description:
 (parforprime, gen, ?gen, gen):void    parforprime_init(&$1, $2, $3, $4)

Function: _parforprime_next
Class: gp2c_internal
Help: Next value for parforprime
Description:
 (parforprime):gen    parforprime_next(&$1)

Function: _parforprime_stop
Class: gp2c_internal
Help: Stop function for parforprime.
Description:
 (parforprime):void    parforprime_stop(&$1)

Function: parforprime
Section: programming/parallel
C-Name: parforprime0
Prototype: vV=GDGJDVDI
Iterator:
 (gen,gen,?gen,closure,?notype) (parforprime, _parforprime_init, _parforprime_next, _parforprime_stop)
Help: parforprime(p=a,{b},expr1,{r},{expr2}):
 evaluates the expression expr1 in parallel for all primes p between a and b
 (if b is set to +oo, the loop will not stop), resulting in as many
 values; if the formal variables r and expr2 are present, evaluate
 sequentially expr2, in which r has been replaced by the different results
 obtained for expr1 and p with the corresponding arguments.
Doc:
 behaves exactly as \kbd{parfor}, but loops only over prime values $p$.
 Precisely, the functions evaluates in parallel the expression \kbd{expr1}
 in the formal
 argument $p$ running through the primes from $a$ to $b$.
 If $b$ is set to \kbd{+oo}, the loop runs indefinitely.
 If $r$ and \kbd{expr2} are present, the expression \kbd{expr2} in the
 formal variables $r$ and $p$ is evaluated with $r$ running through all
 the different results obtained for \kbd{expr1} and $p$ takes the
 corresponding argument.

 It is allowed fo \kbd{expr2} to exit the loop using
 \kbd{break}/\kbd{next}/\kbd{return}; see the remarks in the documentation
 of \kbd{parfor} for details.
