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A list of current NPL keywords.

Keyword Usage
after action time constraint
become state transition
before action time constraint
between action time constraint
const constant definition
else if-else, or a catch-all branch in match statement
final state declaration modifier
function function declaration
guard guard clause
identifier identifier declaration
if if and if-else
is type constraint
init protocol initializer
initial state declaration modifier
match statement branching on actual value type
notification notification declaration
notify notification creation
obligation obligation definition
otherwise obligation consequence
protocol protocol definition
permission permission definition
private protocol member visibility modifier
resume notify callback
require require clause
return return statement
returns return type declaration
state state declaration
struct struct declaration
symbol symbol declaration
this protocol self-reference
union union declaration
update update block