#592 Variable conversion error

[Steve Keen]

"An oldie but a goodie". This turned up when I tried to convert a different variable--the interest rate--from a variable to a parameter.

stock variables in Godley tables cannot be converted to a different type
stock variables in Godley tables cannot be converted to a different type
while executing
"minsky.convertVarType :Loans^CB_S parameter"
("eval" body line 1)
invoked from within
"eval minsky.convertVarType $args"
(procedure "convertVarType" line 1)
invoked from within
"convertVarType [var.valueId] $editVarInput(Type)"
invoked from within
".wiring.editVar.buttonBar.ok invoke"
("uplevel" body line 1)
invoked from within
"uplevel #0 [list $w invoke]"
(procedure "tk::ButtonUp" line 24)
invoked from within
"tk::ButtonUp .wiring.editVar.buttonBar.ok"
(command bound to event)

[High Performance Coder]

But Loans^CB_S appears as a stock variable in the central bank. So the error message is correct.

However, having said that - assuming you renamed the stock variable in the Godley table, then you still cannot change the variable to a paramter. What it really needs to do is have variable name changes in the Godley table affect all of the variables, but a variable name change outside the Godley table should also change the type (ie correctly break the linkage with the Godley table reference).

[High Performance Coder]

I think those changes are sufficiently complex as to need to revisit them for the Quesnay release.

[Steve Keen]

I think it's something different mate--an error unrelated to whether an entity is a Godley Table component or not. Check the attached. I defined a new entity called RR{Buffer} as a way to control when banks reacted to approaching the level at which they're required to have additional reserves. I hadn't yet wired it up to anything, changed it from a flow to a parameter, made it a slider, and then tried to set the slider ranges. That generated this error message:

stock variables in Godley tables cannot be converted to a different type
stock variables in Godley tables cannot be converted to a different type
while executing
"minsky.convertVarType :Dep_HH parameter"
("eval" body line 1)
invoked from within
"eval minsky.convertVarType $args"
(procedure "convertVarType" line 1)
invoked from within
"convertVarType [var.valueId] $editVarInput(Type)"
invoked from within
".wiring.editVar.buttonBar.ok invoke"
("uplevel" body line 1)
invoked from within
"uplevel #0 [list $w invoke]"
(procedure "tk::ButtonUp" line 24)
invoked from within
"tk::ButtonUp .wiring.editVar.buttonBar.ok"
(command bound to event)

But RR{Buffer} is not Dep{HH}, nor is it related to it in any way. So I think this error arises when an attempt to edit one entity is treated as being an attempt to edit another one.

[Steve Keen]

When I wired it up to the relevant block, I found that I could change the slider ranged as I had wished to--no problem.

[Steve Keen]

Here's a screenshot of the relevant block.

[High Performance Coder]

This is quite a different bug to the reported title. Creating https://sourceforge.net/p/minsky/tickets/603/ to track it, as I'd like to fix this for Cantillon.

[High Performance Coder]

Ah - rereading the ticket description - the original report is the different type, the other report is that it should be possible to change the type of a stock variable if that variable name is removed from a Godley table.

[High Performance Coder]

Done now. I've reinstated the exception when trying to convert a variable in a Godley table.