[Newbies] Odd behavior in inject:into: on simple change in Boolean test sequence

Hi folks.

I have a bit of code I am attempting to expand and I am getting strange behavior on a very simple change in structure.

I am parsing '2 * 3 / 2" and returning the product of the terms. Works fine.

Here is the original code. it works as intended.

* result := pairs inject: first into: [ :total :pair | |p| p := pair reject:[:a | a class = OrderedCollection]. (p first = '*') ifTrue: [total := (total * p last )] ifFalse: [ (p last = 0) ifTrue:[^NaNError]. "prevent divide by 0" total := ( total / p last )] ] .*

However, If I make a very simple change to the internal logic by changing the ifTrue: ifFalse: to two separate tests 'total' goes nil on the second pass.

* result := pairs inject: first into: [ :total :pair | |p| p := pair reject:[:a | a class = OrderedCollection]. (p first = '*') ifTrue: [total := (total * p last )] . (p first = '/') ifTrue: [ (p last = 0) ifTrue:[^NaNError]. "prevent divide by 0" total := ( total / p last )] ] .*

it blows up on the second pass as 'total' is Nil and the division throughs a DNU. yet, |p| is populated with #('/' 2)

Thanks in advance

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