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    <p>While OP has already accepted an answer using <code>instance_eval(string)</code>, I would strongly urge OP to avoid string forms of <code>eval</code> unless absolutely necessary. Eval invokes the ruby compiler -- it's expensive to compute and dangerous to use as it opens a vector for code injection attacks.</p> <p>As stated there's no need for send at all:</p> <pre><code>obj.foo.bar </code></pre> <p>If indeed the names of foo and bar are coming from some non-static calculation, then</p> <pre><code>obj.send(foo_method).send(bar_method) </code></pre> <p>is simple and all one needs for this.</p> <p>If the methods are coming in the form of a dotted string, one can use split and inject to chain the methods:</p> <pre><code>'foo.bar'.split('.').inject(obj, :send) </code></pre> <p>Clarifying in response to comments: String eval is one of the riskiest things one can do from a security perspective. If there's any way the string is constructed from user supplied input without incredibly diligent inspection and validation of that input, you should just consider your system owned.</p> <p>send(method) where method is obtained from user input has risks too, but there's a more limited attack vector. Your user input can cause you to execute any 0-arghument method dispatchable through the receiver. Good practise here would be to always whitelist the methods before dispatching:</p> <pre><code>VALID_USER_METHODS = %w{foo bar baz} def safe_send(method) raise ArgumentError, "#{method} not allowed" unless VALID_USER_METHODS.include?(method.to_s) send(method) end </code></pre>
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    1. PORuby nested send
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    1. COA chain of `send` calls based on strings is not much safer than using `eval`.
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      1. USMichaël Witrant
    2. COI agree with both sentiments re security. IMHO, I'd whitelist what could be called both for explicit security reasons and developer maitenence. You're creating a sink hole so be careful around it.
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    3. CO@dbenhur - To Michael's comment - aren't send and inject as bad as eval in terms of security risk? Or is one preferable over the other?
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