Feature #11951
closed
`RubyVM::InstructionSequence.compile` should return the error message within the raised error
Description
When RubyVM::InstructionSequence.compile raises a syntax error, it outputs the syntax error message to $stderr, and then raises a SyntaxError anyway, whose message is simply: "compile error".
I don't think this is useful. For example, if I want to analyze within Ruby code whether a certain string is syntactically correct Ruby code, I would have to reasign $stderr to something such as StringIO.new, run RubyVM::InstructionSequence.compile, rescue the syntax error, (but instead of reading the error message from the error), read the error message by doing $stderr.string. This is cumbersome.
On the other hand, there is eval, which also can raise a SyntaxError. But with eval, the error message comes out with the raised error, and is useful. I don't see any reason why RubyVM::InstructionSequence.compile should behave differently from eval with respect to returning the error message.
I request RubyVM::InstructionSequence.compile to return the error message as the message on the raised error rather than directly printing it to $stderr.
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