Issue #12093 has been updated by Nobuyoshi Nakada.


I discovered an old [patch] for this issue.
This enables the following code, but doesn't seem useful to me.

```ruby
obj = Struct.new(:a, :b).new(1, 2)
bind = obj.instance_eval {binding}
RubyVM::InstructionSequence.compile("a + b").eval_with(bind) #=> 3
```

[patch]: https://github.com/ruby/ruby/compare/trunk...nobu:feature/12093-iseq-eval_with

----------------------------------------
Feature #12093: Eval InstructionSequence with binding
https://bugs.ruby-lang.org/issues/12093#change-60714

* Author: Pavel Evstigneev
* Status: Open
* Priority: Normal
* Assignee: 
----------------------------------------
Implementing this feature can boost template engine performance

Currently Kernel#eval can accept binding argument, so code running with eval will have access to local variables and current instance. This feature used by template languages

ERB: https://github.com/ruby/ruby/blob/trunk/lib/erb.rb#L887
Erubis: Can't find code on github, but it uses instance_eval or Kernel#eval
Haml: https://github.com/haml/haml/blob/master/lib/haml/engine.rb#L115

My proposal is to make RubyVM::InstructionSequence#eval to recieve binding argument. So it can be used for caching templates. As I see from ERB and Haml, cached template is stored as ruby code string, every time when we render template that string (ruby code) is evaluated, internally ruby will parse it into RubyVM::InstructionSequence and then evaluate.

Before I try to implement it myself in ruby, but could not. Lack of experience with C https://github.com/Paxa/ruby/commit/f5b602b6d9eada9675a4c002c9a5a79129df73a6 (not working)



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