Support for backtick literals

Author: xitology

docs/src/test.md

@@ -377,6 +377,7 @@ is supported.
         Base.show(Base.stdout)
         Base.@show Base.stdout
         println("x = $x")
+        `echo "hello \`world\`"`
         "Compute nothing"
         function f(::Number)
             return
@@ -480,6 +481,8 @@ is supported.
 
         println("x = $(x)")
 
+        `echo "hello \`world\`"`
+
         "Compute nothing"
         function f(::Number)
             return nothing

src/expr.jl

@@ -176,6 +176,8 @@ function tile_expr(ex::Expr, pr = -1)
         return tile_expr_function(head, decl, body)
     elseif (@isexpr ex Expr(:macrocall, ref::GlobalRef, docstr::String, def)) && ref === GlobalRef(Core, Symbol("@doc"))
         return tile_expr(docstr, pr) / tile_expr(def, pr)
+    elseif (@isexpr ex Expr(:macrocall, ref::GlobalRef, str::String)) && ref === GlobalRef(Core, Symbol("@cmd"))
+        return literal("`") * literal(escape_string(str, "`")) * literal("`")
     elseif @isexpr ex Expr(head := :break || :continue || :return)
         return literal(head)
     elseif @isexpr ex Expr(head := :return || :const, arg)