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copied!<p><code>ToExpression</code> uses the current binding of <code>$Context</code> when creating symbols, so you can force your expression to be interpreted within a particular context thus:</p> <pre><code>Block[{$Context="MyPackage`Private`"}, ToExpression[#][5]] & /@ tests </code></pre> <p>I'm not sure I understand the circumstances of the original question. You can get the current context using <code>$Context</code> or <code>Context[]</code>... but <code>ToExpression</code> will automatically use the current context without intervention.</p> <p>If I run the exhibited code in a notebook, it works fine. If I run it like this:</p> <pre><code>Begin["MyPackage`Private`"] test1[g_] := (g == 5); test2[g_] := (g == 6); tests = {"test1", "test2"} ToExpression[#][5] & /@ tests End[] </code></pre> <p>... it also works fine. I can get it to fail if I run it like this:</p> <pre><code>(* in the package file *) Begin["MyPackage`Private`"] test1[g_] := (g == 5); test2[g_] := (g == 6); End[] (* in the notebook *) tests = {"test1", "test2"} ToExpression[#][5] & /@ tests </code></pre> <p>... which not only fails but also creates spurious symbols in the notebook's context. You can work around this problem using the <code>Block</code> recipe from above.</p> <p>If you want to capture the context that was in effect at the moment the package code was loaded, you can do something like this:</p> <pre><code>(* in the package *) Begin["MyPackage`Private`"] test1[g_] := (g == 5); test2[g_] := (g == 6); tests = {"test1", "test2"}; With[{context = $Context}, runTests[] := Block[{$Context = context}, ToExpression[#][5]] & /@ tests ] End[] (* in the notebook *) MyPackage`Private`runTests[] </code></pre> <p><code>runTests</code> uses <code>With</code> to inject the private package context into its definition.</p> <p>As Janus' noted, it is better to use symbols than strings since they automatically manage the whole context issue -- but this assumes your actual use case will permit the use of symbols.</p>

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