builder-generated scripts should not /initialise/ components with thisTrial['blah']

[peircej]

When a component is going to use a parameter that gets set every trial then it needn't be initialised to that value. Just initialise with default and set later to the necessary value. This has the advantage that we can create the parameter variables (e.g. thisTrial['ori']) just before the loops, rather than at the start of the script.

Not sure though. Is it worth the effort for some slightly better code? Does it /matter/ if the TrialHandler is created at the start of the experiment rather then just before it runs?

[peircej]

I didn't explain my concern about this very well - the downside is the code for working out how to write the script will get rather more confusing (even though it should be reasonably easy to write first time) and maybe it isn't worth having confusing internal code for a non-critical feature like this.

[jeremygray]

I am not completely sure if its related, but it might be useful in this situation (which came up for me and also someone else at the workshop): if you set a component's value (via a code snippet in a field in a builder window) to $value at the start of a routine, you get an error at initialization time (because the variable is unknown at that point). the non-obvious work around I used was to set value=None at the start of the experiment via a code component (so that variable "value" would be defined, even if its value was meaningless). so it sounds like only expecting things to be defined at the start of the routine would be good?

[peircej]

Yes, this is the same issue, and I've also been seeing it more and more as an issue. You got the correct workaround too, but it's kind of ugly. I've promoted the issue to 3 ticks.

[peircej]

Done (commit fe253ea)