Trying

Wolf’s type system ensures all data processed by a program meets a certain set of restrictions. By default, inputs that don’t meet those restrictions will cause a compiler error.

Instead of erroring, try statements allow code to explicitly handle data that does not meet those restrictions.

Basic use

try expressions are formed like if expressions:

• The try keyword.
• An “attempt” expression that might not type check.
• The else keyword.
• A default expression to be used when the attempt block does not type check.

-- If `user_config` has a type which can satisfy this expression, then it will be run.
-- Otherwise, the default value of 1000 will be used.
let timeout = try user_config.service.timeout else 1000

Multiple expressions

Multiple try sections can be added, similarly to an if expression, to define a series of fallback expressions.

-- The expressions are attempted in order of appearance.
let timeout = 
	try workspace_config.service.timeout
	try folder_config.service.timeout
	try user_config.service.timeout
	else 1000