Alternative to creating references to non-objects #149
Comments
|
How about storing the arguments in a JS array and then creating a reference
to the array. Below is the pseudocode skeleton:
```c
napi_create_array();
for (index = 0; index < argc; index++) {
napi_set_element(array, index, argv[index]);
}
napi_create_reference(array, &array_ref);
```
…On Fri, Sep 29, 2017 at 11:49 AM, Mika Fischer ***@***.***> wrote:
nodejs/node#15289 <nodejs/node#15289> removed the
possibility to create references to values that are not objects.
My use-case is the following. I want to store arguments given to my
function persistently. Then some time later I want to call a callback
function with those parameters. In the past I just used a
vector<Reference<Value>>. Now I don't quite understand how I'm supposed
to do it...
As an example, see this test: https://github.com/mika-
fischer/napi-thread-safe-callback/blob/e03dda83fb1d2a63fb8332406e2436
fc18a63fba/test/tests.cpp#L36-L51
—
You are receiving this because you are subscribed to this thread.
Reply to this email directly, view it on GitHub
<#149>, or mute the thread
<https://github.com/notifications/unsubscribe-auth/AA7k0R_0u2jIKmgFqS4_joy9vjAFLR7vks5snK8cgaJpZM4PoYFz>
.
|
|
OK, fair enough, that's slightly inconcenient, but not too bad... But just so I understand: There's now no way at all to just hold onto say a string literal across calls into C++? |
|
There is. You can convert it to a `char *` and then pass the `char *` to
`napi_wrap()`. In general, you need to convert to a native type, store the
data in a heap-allocated buffer, and use `napi_wrap()`.
…On Fri, Sep 29, 2017 at 1:17 PM, Mika Fischer ***@***.***> wrote:
OK, fair enough, that's slightly inconcenient, but not too bad...
But just so I understand: There's now no way at all to just hold onto say
a string literal across calls into C++?
—
You are receiving this because you commented.
Reply to this email directly, view it on GitHub
<#149 (comment)>,
or mute the thread
<https://github.com/notifications/unsubscribe-auth/AA7k0X7gRpG7-BD63rsy-k1FGKdGbZkcks5snMPPgaJpZM4PoYFz>
.
|
|
Sure, I meant keeping the JS string without converting to C++. That seems impossible now, right? And while converting a string to C++ by itself is not that bad, in cases like this where you get passed a |
|
It is indeed more complicated. Nevertheless, it is necessary, because not
all engines support making references to non-object types.
…On Fri, Sep 29, 2017 at 1:51 PM, Mika Fischer ***@***.***> wrote:
Sure, I meant keeping the JS string without converting to C++. That seems
impossible now, right?
And while converting a string to C++ by itself is not that bad, in cases
like this where you get passed a Value and you don't care what it is, you
just want to hold on to it for later use, things are a lot more complicated
than before if you don't want to use this boxing trick...
—
You are receiving this because you commented.
Reply to this email directly, view it on GitHub
<#149 (comment)>,
or mute the thread
<https://github.com/notifications/unsubscribe-auth/AA7k0Yh1YomF_IR2IaoYrIa4Kv9JZAUWks5snMupgaJpZM4PoYFz>
.
|
|
Ah I see, that makes sense then. Thanks for the explanations! |
Sign up for free
to join this conversation on GitHub.
Already have an account?
Sign in to comment
nodejs/node#15289 removed the possibility to create references to values that are not objects.
My use-case is the following. I want to store arguments given to my function persistently. Then some time later I want to call a callback function with those parameters. In the past I just used a
vector<Reference<Value>>. Now I don't quite understand how I'm supposed to do it...As an example, see this test: https://github.com/mika-fischer/napi-thread-safe-callback/blob/e03dda83fb1d2a63fb8332406e2436fc18a63fba/test/tests.cpp#L36-L51
The text was updated successfully, but these errors were encountered: