saveVar / Workspace

Instructions in a transaction execute as a batch. saveVar captures an instruction’s output so later instructions can reference it.

saveVar

builder
  .callMethod({ componentAddress: accountAddress, methodName: "withdraw" }, [
    { Literal: resourceAddress },
    { Literal: "10" },
  ])
  .saveVar("bucket");

This saves the result of the withdraw call to a workspace variable named "bucket".

Referencing workspace variables

Use { Workspace: "name" } in any argument position to reference a saved variable:

builder.callMethod({ componentAddress: accountAddress, methodName: "deposit" }, [{ Workspace: "bucket" }]);

The builder resolves string workspace names to numeric IDs internally.

Accessing tuple fields

Some methods return multiple values. You can address individual fields using .0, .1, etc.:

builder
  .callMethod({ componentAddress: poolComponent, methodName: "remove_liquidity" }, [{ Workspace: "tokens_lp" }])
  .saveVar("buckets")
  .callMethod({ componentAddress: accountAddress, methodName: "deposit" }, [{ Workspace: "buckets.0" }])
  .callMethod({ componentAddress: accountAddress, methodName: "deposit" }, [{ Workspace: "buckets.1" }]);

Workspace references in callMethod

You can also call methods on workspace-stored components:

builder
  .callFunction({ templateAddress, functionName: "new" }, [])
  .saveVar("component")
  .callMethod({ fromWorkspace: "component", methodName: "init" }, [{ Literal: "arg" }]);