macro args have different types in MacroExpand

[guoshimin]

Given the following basic macro definition

:import (
  "fmt"
  "go/ast"
)

:macro myMacro(arg ast.Node) ast.Node {
  fmt.Printf("arg has type %T\n", arg)
  return ~'{1}
}

When applied directly in the REPL, I got

gomacro> myMacro; foo
arg has type *ast.Ident
{int 1}	// untyped.Lit

When used inside MacroExpand, I got

gomacro> MacroExpand(~'{myMacro; foo})
arg has type *ast.ExprStmt
1	// go/ast.Node
true	// bool

It makes it hard to write macro code that works both when being applied directly and when inside MacroExpand. Is this an issue or do I have some wrong preconception on how things are supposed to work?

[cosmos72]

Usually there is no need to look inside the arguments passed to a macro - you simply insert them into a larger AST fragment.
As long as doing that works, the concrete type of an argument does not matter much.

The difference you observe is because it's not possible to directly insert an *ast.Ident inside an *ast.BlockStmt - it must be wrapped (at least) in an *ast.ExprStmt