How can I compile a script that has some dynamic code?

user_1004787 0
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I want to compile this script:

Red [File: %b.red]
context [
    a: 123
    hidden: 999
    set 'global-exports context [
        export-a: a
    ]
]
probe global-exports

But I get an error when trying to compile it with $ ./red-13oct19-a4ee537c -r b.red:

*** Red Compiler Internal Error: Script Error : Invalid path value: global-exports 
*** Where: register-object 
*** Near:  [objects/context/global-exports: make object! [
a: none
hidden: none
]]
red jit interpreter dynamic compilation
1 Answers

In general, you can wrap dynamic code with do [...] function, which treats a block of code like data and uses an interpreter to launch it at runtime:

Red [File: %b.red]
context [
    a: 123
    hidden: 999
    do [   ;-- the code inside is run by interpreter at runtime
        set 'global-exports context [
            export-a: a
        ]
    ]
]
probe get 'global-exports   ;-- dynamic retrieval

You also have to retrieve values dynamically, unless you initialize it statically (e.g. global-exports: none) somewhere earlier.

In this particular case also exchanging context with make object! will be sufficient:

Red [File: %b.red]
context [
    a: 123
    hidden: 999
    set 'global-exports make object! [
        export-a: a
    ]
]
probe global-exports

Compiling dynamic code will be possible with JIT compiler, which is planned in future, but not before Red version 1.0.

(thanks @9214 and @hiiamboris for the ideas on red/help gitter chat)

user_10047870
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