1 line
22 KiB
JavaScript
1 line
22 KiB
JavaScript
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punctuation"}},[t._v(",")]),t._v(" "),s("span",{pre:!0,attrs:{class:"token class-name"}},[t._v("Counter")]),s("span",{pre:!0,attrs:{class:"token operator"}},[t._v(">")]),s("span",{pre:!0,attrs:{class:"token punctuation"}},[t._v(",")]),t._v("\n "),s("span",{pre:!0,attrs:{class:"token keyword"}},[t._v("pub")]),t._v(" authority"),s("span",{pre:!0,attrs:{class:"token punctuation"}},[t._v(":")]),t._v(" "),s("span",{pre:!0,attrs:{class:"token class-name"}},[t._v("Signer")]),s("span",{pre:!0,attrs:{class:"token operator"}},[t._v("<")]),s("span",{pre:!0,attrs:{class:"token lifetime-annotation symbol"}},[t._v("'info")]),s("span",{pre:!0,attrs:{class:"token operator"}},[t._v(">")]),s("span",{pre:!0,attrs:{class:"token punctuation"}},[t._v(",")]),t._v("\n"),s("span",{pre:!0,attrs:{class:"token punctuation"}},[t._v("}")]),t._v("\n")])])]),s("p",[t._v("Here, a couple "),s("code",[t._v("#[account(..)]")]),t._v(" attributes are used.")]),t._v(" "),s("ul",[s("li",[s("code",[t._v("mut")]),t._v(": tells the program to persist all changes to the account.")]),t._v(" "),s("li",[s("code",[t._v("has_one")]),t._v(": enforces the constraint that "),s("code",[t._v("Increment.counter.authority == Increment.authority.key")]),t._v(".")])]),t._v(" "),s("p",[t._v("Another new concept here is the "),s("code",[t._v("Signer")]),t._v(" type. This enforces the constraint that the "),s("code",[t._v("authority")]),t._v("\naccount "),s("strong",[t._v("signed")]),t._v(" the transaction. However, anchor doesn't fetch the data on that account.")]),t._v(" "),s("p",[t._v("If any of these constraints do not hold, then the "),s("code",[t._v("increment")]),t._v(" instruction will never be executed.\nThis allows us to completely separate account validation from our program's business logic, allowing us\nto reason about each concern more easily. For more, see the full "),s("a",{attrs:{href:"https://docs.rs/anchor-lang/latest/anchor_lang/derive.Accounts.html",target:"_blank",rel:"noopener noreferrer"}},[t._v("list"),s("OutboundLink")],1),t._v(" of account constraints.")]),t._v(" "),s("h2",{attrs:{id:"next-steps"}},[s("a",{staticClass:"header-anchor",attrs:{href:"#next-steps"}},[t._v("#")]),t._v(" Next Steps")]),t._v(" "),s("p",[t._v("We've covered the basics for writing a single program using Anchor on Solana. But the power of\nblockchains come not from a single program, but from combining multiple "),s("em",[t._v("composable")]),t._v(" programs\n(buzzword...check). Next, we'll see how to call one program from another.")])])}),[],!1,null,null,null);a.default=e.exports}}]); |