Blueprint for managing randomness

globals [
 current-seed
]

to setup
  clear-all
  reset-ticks

  manage-randomness
end 

to manage-randomness
; This procedure checks if the user wants to use a new seed given by the 'new-seed' primitive, or if
; they want to use a custom-defined seed. In the latter case, the custom-defined seed is retrieved
; from the 'custom-seed' global variable, which is set in the Interface in the input box. Such variable
; can be defined either manually by the user, or through the 'save-current-seed-as-custom' button (see
; the 'save-current-seed-as-custom' procedure below).
; In either case, this selection is mediated by the 'current-seed' global variable. This is because
; having a global variable storing the value that will be passed to the 'random-seed' primitive is the
; only way to [1] have such value displayed in the Interface, and [2] re-use such value in case the
; user wants to perform 'save-current-seed-as-custom'.

  ifelse (use-custom-seed?)
   [set current-seed custom-seed]
   [set current-seed new-seed]

  random-seed current-seed
end 

to save-current-seed-as-custom
; This procedure lets the user store the seed that was used in the current run (and stored in the
; 'random-seed' global variable; see comment in 'manage-randomness') as 'custom-seed', which will
; allow such value to be re-used after turning on the 'use-custom-seed?' switch in the Interface.

  set custom-seed current-seed
end 

to go
; The first if-statement allows the user to bring the run to a custom-defined ticks value.
; The custom-defined ticks value is retrieved from the 'custom-ticks' global variable,
; which is set in the Interface in the input box. Such variable can be defined either
; manually by the user, or through the 'save-current-ticks-as-custom' button (see the
; 'save-current-ticks-as-custom' procedure above).

  if (use-custom-ticks?) AND (ticks = custom-ticks) [stop]

  ; Insert here the normal 'go' procedure.

  tick
end 

to save-current-ticks-as-custom
; This procedure lets the user store the current 'ticks' value as 'custom-ticks'. This will allow
; the user, after switching on the 'use-custom-ticks?' switch, to bring the simulation to the
; exact same ticks as when the 'save-current-ticks-as-custom' button was used. If used in combination
; with the 'save-current-seed-as-custom' button and 'use-custom-seed?' switch, this allows the user
; to surely and quickly jump to the exact same situation as when a previous simulation was interrupted.

  set custom-ticks ticks
end