Use 'emit --info', 'emit --verbose', ... (#69)

examples/ui.toit

@@ -6,16 +6,16 @@ import cli show *
 
 some-chatty-method cli/Cli:
   ui := cli.ui
-  ui.debug "This is a debug message."
-  ui.verbose "This is a verbose message."
-  ui.inform "This is an information message."
-  ui.warn "This is a warning message."
-  ui.error "This is an error message."
-  ui.interactive "This is an interactive message."
+  ui.emit --debug "This is a debug message."
+  ui.emit --verbose "This is a verbose message."
+  ui.emit --info "This is an information message."
+  ui.emit --warning "This is a warning message."
+  ui.emit --error "This is an error message."
+  ui.emit --interactive "This is an interactive message."
   // By convention, 'result' calls should only happen in the method that
   // initially received the Invocation object.
   // For demonstration purposes, we call it here.
-  ui.result "This is a result message."
+  ui.emit --result "This is a result message."
 
 emit-structured cli/Cli:
   ui := cli.ui

src/parser_.toit

@@ -37,7 +37,7 @@ class Parser_:
     // Otherwise, ignore the ui that was determined through the command line and
     // print the usage on stderr, followed by an exit 1.
     ui := test-ui_ or (Ui --level=Ui.QUIET-LEVEL --printer=StderrPrinter_)
-    ui.error str
+    ui.emit --error str
     help-command_ path [] --invoked-command=invoked-command_ --ui=ui
     ui.abort
     unreachable