Pragmatic directives cause the language to operate in a specific manner,   allowing support for operational variances within the program code   (possibly by the loading of specific or alternative modules).



Task

List any pragmatic directives supported by the language,   and demonstrate how to activate and deactivate the pragmatic directives and to describe or demonstrate the scope of effect that the pragmatic directives have within a program.




9!:1 random seed (incomplete specification of state -- see 9!:45)
9!:3 default display for non-nouns
9!:7 box drawing characters
9!:9 error messages
9!:11 print precision
9!:17 centering (or not) when box contents are smaller than boxes 
9!:19 comparison tolerance
9!:21 memory limit
9!:25 security level
9!:27 text of immediate execution phrase
9!:29 enable immediate execution phrase
9!:33 execution time limit
9!:35 disable (or re-enable) assertions
9!:37 output control
9!:39 locales' hash table size
9!:41 retain (or not) whitespace and comments in explicit definitions
9!:43 which random number generator to use?
9!:45 what is the current state of that rng?
9!:49 enable reserved words for argument names 
