Synopsis The special variable it occurs outside a reducer expression.
Description A Rascal:Reducer is used to reduce all elements in a collection to a sngle value. The special variable it represents the currently reduced value and can be modified inside the reducer. This error is generated when it i used otuside the a reducer.

  • You have accidentially used a variable with the name it; rename your variable to something else.
  • Place the expression that contains it in a reducer expression.
Examples This is correct way to add all elements in a list:
rascal>(0 | it + n | int n <- [1,5,9] )
int: 15
Using it outside a reducer gives an error:
rascal>it + 3
|stdin:///|(0,2,<1,0>,<1,2>): Use of 'it' special variable is only allowed within reducers
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