Styjun

My colleague treats me like he's my boss, yet we're on the same level

Necessity of tenure for lifetime academic research

Moscow SVO airport, how to avoid scam taxis without pre-booking?

Properly unlinking hard links

Using font to highlight a god's speech in dialogue

What caused the end of cybernetic implants?

how can reincarnation magic be limited to prevent overuse?

How can I improve my formal definitions?

Why do motor drives have multiple bus capacitors of small value capacitance instead of a single bus capacitor of large value?

Ways you can end up paying interest on a credit card if you pay the full amount back in due time

What are ways to record who took the pictures if a camera is used by multiple people?

Padding a column of lists

How can I store milk for long periods of time?

Can a system of three stars exist?

What is the motivation behind designing a control stick that does not move?

Could a complex system of reaction wheels be used to propel a spacecraft?

An idiom for “Until you punish the offender, they will not give up offenses”

Don't look at what I did there

How smart contract transactions work?

awk print conditions

Heuristic argument for the Riemann Hypothesis

How were US credit cards verified in-store in the 1980's?

Can I leave a large suitcase at TPE during a 4-hour layover, and pick it up 4.5 days later when I come back to TPE on my way to Taipei downtown?

Should a TA point out a professor's mistake while attending their lecture?

Kotlin reflection/dynamic function call in multi-platform environment

Moshi's Custom Adapter with RxAndroid & Retrofit & KotlinHow to get enum value of raw type from an enum class and a string in kotlinKotlin reflection error when calling functioninvoke() on out-projected Function objectKotlin - Multi platform featurekotlin : cannot parse string to enum with JacksonKotlin - specify type explicitly in IntelliJ after extracting a variable shortcutKotlin: enums with associated values; function inside 'enum entry' gets `unresolved reference` errorKotlin ReflectionHow to safely cast a reflected class in Kotlin

.everyoneloves__top-leaderboard:empty,.everyoneloves__mid-leaderboard:empty,.everyoneloves__bot-mid-leaderboard:empty margin-bottom:0;

1

Given

class X 
 fun f() ...
 fun g() ...
 ...

I would like to call f, g, or other class function by name, which is known dynamically at runtime. This is possible with kotlin-reflection, e.g.

val callback : KCallable<*>? = X::class.members.firstOrNull it.name == predVar 
if (callback != null) {
 callback.call(obj, ...)

The only snag here is that my multiplatform application has targets other than JVM. For instance, is kotlin reflection doable in javascript? Certainly, JS is dynamically typed language, thus my question is if it is already implemented there.

Alternatively, I can have a collection, or map of those functions. What would be the most elegant syntax of defining a list of functions, and having them callable dynamically? For example, given several enum type attributes, I can make a bunch of Boolean methods like this

var booleanDerivatives = hashMapOf<String, () -> Boolean>(
 "breaksAfterComma" to fun (): Boolean 
 return options[breaksComma] === Breaks.After
 
 ,"breaksBeforeComma" to fun (): Boolean 
 return options[breaksComma] === Breaks.Before
 
 ,"breaksAfterLogicalConjunction" to fun (): Boolean 
 return options[breaksAroundLogicalConjunctions] === Breaks.After 
 
)

However, unlike reflection, I seem to have to use string literals, because without reflection there is no mechanism translating a name into a string. Or there is?

kotlin

share|improve this question

edited Mar 28 at 19:22

Tegiri Nenashi

asked Mar 27 at 23:55

Tegiri NenashiTegiri Nenashi

2,70622 gold badges1414 silver badges1818 bronze badges

• 
  
  
  

  
  1
  

  
  
  
  
  
  

  
  
  Wouldn't expect/actual keywords help in your case?
  
  – yegodm
  Mar 28 at 19:51
  

  
  
  
  


• 
  
  
  

  
  

  
  
  
  
  
  

  
  
  There are two parts of my question, and while Paul answered the first one, the second part is open. I assume your expect/actual hint relates to the first part; that is rolling out DIY implementation of reflection which is standard kotlin reflection in JVM env, and reflection proxy in JS via some sort of dynamic calls. Anyway, I have decided to follow the second venue outlined in my post and create a map of functions, as in the second code snippet. My minor gripe about this solution is that the "names" of the methods are string literals, which is probably not big deal at all.
  
  – Tegiri Nenashi
  Mar 29 at 0:49
  
  

  
  
  
  

add a comment | 

1

Given

class X 
 fun f() ...
 fun g() ...
 ...

I would like to call f, g, or other class function by name, which is known dynamically at runtime. This is possible with kotlin-reflection, e.g.

val callback : KCallable<*>? = X::class.members.firstOrNull it.name == predVar 
if (callback != null) {
 callback.call(obj, ...)

The only snag here is that my multiplatform application has targets other than JVM. For instance, is kotlin reflection doable in javascript? Certainly, JS is dynamically typed language, thus my question is if it is already implemented there.

Alternatively, I can have a collection, or map of those functions. What would be the most elegant syntax of defining a list of functions, and having them callable dynamically? For example, given several enum type attributes, I can make a bunch of Boolean methods like this

var booleanDerivatives = hashMapOf<String, () -> Boolean>(
 "breaksAfterComma" to fun (): Boolean 
 return options[breaksComma] === Breaks.After
 
 ,"breaksBeforeComma" to fun (): Boolean 
 return options[breaksComma] === Breaks.Before
 
 ,"breaksAfterLogicalConjunction" to fun (): Boolean 
 return options[breaksAroundLogicalConjunctions] === Breaks.After 
 
)

However, unlike reflection, I seem to have to use string literals, because without reflection there is no mechanism translating a name into a string. Or there is?

kotlin

share|improve this question

edited Mar 28 at 19:22

Tegiri Nenashi

asked Mar 27 at 23:55

Tegiri NenashiTegiri Nenashi

2,70622 gold badges1414 silver badges1818 bronze badges

• 
  
  
  

  
  1
  

  
  
  
  
  
  

  
  
  Wouldn't expect/actual keywords help in your case?
  
  – yegodm
  Mar 28 at 19:51
  

  
  
  
  


• 
  
  
  

  
  

  
  
  
  
  
  

  
  
  There are two parts of my question, and while Paul answered the first one, the second part is open. I assume your expect/actual hint relates to the first part; that is rolling out DIY implementation of reflection which is standard kotlin reflection in JVM env, and reflection proxy in JS via some sort of dynamic calls. Anyway, I have decided to follow the second venue outlined in my post and create a map of functions, as in the second code snippet. My minor gripe about this solution is that the "names" of the methods are string literals, which is probably not big deal at all.
  
  – Tegiri Nenashi
  Mar 29 at 0:49
  
  

  
  
  
  

add a comment | 

Given

class X 
 fun f() ...
 fun g() ...
 ...

I would like to call f, g, or other class function by name, which is known dynamically at runtime. This is possible with kotlin-reflection, e.g.

val callback : KCallable<*>? = X::class.members.firstOrNull it.name == predVar 
if (callback != null) {
 callback.call(obj, ...)

The only snag here is that my multiplatform application has targets other than JVM. For instance, is kotlin reflection doable in javascript? Certainly, JS is dynamically typed language, thus my question is if it is already implemented there.

Alternatively, I can have a collection, or map of those functions. What would be the most elegant syntax of defining a list of functions, and having them callable dynamically? For example, given several enum type attributes, I can make a bunch of Boolean methods like this

var booleanDerivatives = hashMapOf<String, () -> Boolean>(
 "breaksAfterComma" to fun (): Boolean 
 return options[breaksComma] === Breaks.After
 
 ,"breaksBeforeComma" to fun (): Boolean 
 return options[breaksComma] === Breaks.Before
 
 ,"breaksAfterLogicalConjunction" to fun (): Boolean 
 return options[breaksAroundLogicalConjunctions] === Breaks.After 
 
)

However, unlike reflection, I seem to have to use string literals, because without reflection there is no mechanism translating a name into a string. Or there is?

kotlin

share|improve this question

edited Mar 28 at 19:22

Tegiri Nenashi

asked Mar 27 at 23:55

Tegiri NenashiTegiri Nenashi

2,70622 gold badges1414 silver badges1818 bronze badges

class X 
 fun f() ...
 fun g() ...
 ...

val callback : KCallable<*>? = X::class.members.firstOrNull it.name == predVar 
if (callback != null) {
 callback.call(obj, ...)

var booleanDerivatives = hashMapOf<String, () -> Boolean>(
 "breaksAfterComma" to fun (): Boolean 
 return options[breaksComma] === Breaks.After
 
 ,"breaksBeforeComma" to fun (): Boolean 
 return options[breaksComma] === Breaks.Before
 
 ,"breaksAfterLogicalConjunction" to fun (): Boolean 
 return options[breaksAroundLogicalConjunctions] === Breaks.After 
 
)

share|improve this question

edited Mar 28 at 19:22

Tegiri Nenashi

asked Mar 27 at 23:55

Tegiri NenashiTegiri Nenashi

2,70622 gold badges1414 silver badges1818 bronze badges

share|improve this question

edited Mar 28 at 19:22

Tegiri Nenashi

asked Mar 27 at 23:55

Tegiri NenashiTegiri Nenashi

2,70622 gold badges1414 silver badges1818 bronze badges

asked Mar 27 at 23:55

Tegiri NenashiTegiri Nenashi

2,70622 gold badges1414 silver badges1818 bronze badges

asked Mar 27 at 23:55

Tegiri NenashiTegiri Nenashi

2,70622 gold badges1414 silver badges1818 bronze badges

1 Answer
1

active

oldest

votes

1

According to the docs, no you can't access methods via reflection in the JS target. You would need to maintain your own collection of function references to achieve what you describe across both JVM and JS targets.

share|improve this answer

answered Mar 28 at 0:19

Paul HicksPaul Hicks

9,95133 gold badges3131 silver badges5858 bronze badges

add a comment | 

Your Answer

StackExchange.ifUsing("editor", function ()
StackExchange.using("externalEditor", function ()
StackExchange.using("snippets", function ()
StackExchange.snippets.init();
);
);
, "code-snippets");

StackExchange.ready(function()
var channelOptions =
tags: "".split(" "),
id: "1"
;
initTagRenderer("".split(" "), "".split(" "), channelOptions);

StackExchange.using("externalEditor", function()
// Have to fire editor after snippets, if snippets enabled
if (StackExchange.settings.snippets.snippetsEnabled)
StackExchange.using("snippets", function()
createEditor();
);

else
createEditor();

);

function createEditor()
StackExchange.prepareEditor(
heartbeatType: 'answer',
autoActivateHeartbeat: false,
convertImagesToLinks: true,
noModals: true,
showLowRepImageUploadWarning: true,
reputationToPostImages: 10,
bindNavPrevention: true,
postfix: "",
imageUploader:
brandingHtml: "Powered by u003ca class="icon-imgur-white" href="https://imgur.com/"u003eu003c/au003e",
contentPolicyHtml: "User contributions licensed under u003ca href="https://creativecommons.org/licenses/by-sa/3.0/"u003ecc by-sa 3.0 with attribution requiredu003c/au003e u003ca href="https://stackoverflow.com/legal/content-policy"u003e(content policy)u003c/au003e",
allowUrls: true
,
onDemand: true,
discardSelector: ".discard-answer"
,immediatelyShowMarkdownHelp:true
);



);

draft saved

draft discarded

Sign up or log in

StackExchange.ready(function ()
StackExchange.helpers.onClickDraftSave('#login-link');
);

Sign up using Google

Sign up using Facebook

Sign up using Email and Password

Post as a guest

Name

Email

Required, but never shown

StackExchange.ready(
function ()
StackExchange.openid.initPostLogin('.new-post-login', 'https%3a%2f%2fstackoverflow.com%2fquestions%2f55388219%2fkotlin-reflection-dynamic-function-call-in-multi-platform-environment%23new-answer', 'question_page');

);

Post as a guest

Name

Email

Required, but never shown

1

According to the docs, no you can't access methods via reflection in the JS target. You would need to maintain your own collection of function references to achieve what you describe across both JVM and JS targets.

share|improve this answer

answered Mar 28 at 0:19

Paul HicksPaul Hicks

9,95133 gold badges3131 silver badges5858 bronze badges

add a comment | 

1

According to the docs, no you can't access methods via reflection in the JS target. You would need to maintain your own collection of function references to achieve what you describe across both JVM and JS targets.

share|improve this answer

answered Mar 28 at 0:19

Paul HicksPaul Hicks

9,95133 gold badges3131 silver badges5858 bronze badges

add a comment | 

According to the docs, no you can't access methods via reflection in the JS target. You would need to maintain your own collection of function references to achieve what you describe across both JVM and JS targets.

share|improve this answer

answered Mar 28 at 0:19

Paul HicksPaul Hicks

9,95133 gold badges3131 silver badges5858 bronze badges

share|improve this answer

answered Mar 28 at 0:19

Paul HicksPaul Hicks

9,95133 gold badges3131 silver badges5858 bronze badges

answered Mar 28 at 0:19

Paul HicksPaul Hicks

9,95133 gold badges3131 silver badges5858 bronze badges

answered Mar 28 at 0:19

Paul HicksPaul Hicks

9,95133 gold badges3131 silver badges5858 bronze badges