Feature #11951: `RubyVM::InstructionSequence.compile` should return the error message within the raised error

• Status: Closed
• Assignee: -
• Target version: -

[sawa (Tsuyoshi Sawada)]

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.

[nobu (Nobuyoshi Nakada)]

• Is duplicate of Feature #11868: Proposal for RubyVM::InstructionSequence.compile to return an object containing the syntax error information currently written to STDERR added

[nobu (Nobuyoshi Nakada)]

• Is duplicate of deleted (Feature #11868: Proposal for RubyVM::InstructionSequence.compile to return an object containing the syntax error information currently written to STDERR)

[nobu (Nobuyoshi Nakada)]

• Related to Feature #11868: Proposal for RubyVM::InstructionSequence.compile to return an object containing the syntax error information currently written to STDERR added

[nobu (Nobuyoshi Nakada)]

https://github.com/ruby/ruby/compare/trunk...nobu:feature/11951-iseq-compile-error

[nobu (Nobuyoshi Nakada)]

• Status changed from Open to Closed

Applied in changeset r54189.

---

SyntaxError message at iseq compile

• iseq.c (rb_iseq_compile_with_option): make the parser in mild
  error.
• load.c (rb_load_internal0): ditto.
• parse.y (yycompile0): return the error message within the error
  to be raised. [Feature #11951]
• parse.y (parser_compile_error): accumulate error messages in the
  error_buffer.