localization - Conflict with variables in pure functions

Consider the following snippet of code.

Clear[f, g]
f[x_] := Function[{i}, x];
g[h_] := Module[{Z},
   Z[i_] := Print[h];
   Print[h];
   Z[1];
];

When g[f[2]] is called, the first Print correctly returns Function[{i$},2], while the second Print returns an error with Function[{1},2] as the output. The error arises from a conflict between the two local variables i's in f and Z. In general, Mathematica automatically renames variables to avoid conflict, as described here.

Why is there a conflict in this case? Other than choosing an alternative variable name, what are the useful guidelines one should follow to avoid such conflicts?

Answer

Using

SetSystemOptions["StrictLexicalScoping" -> True]

will fix this.

Related (long reading!):

Comments

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