What is the proper way of doing partial matches in Scala? -

i have properties object, , want if configuration contains specific key. if key not exist, want ignore it. tried following way:

myprops getproperty "foo" match {   case v if v != null => dosomethingwith v } 

but causes matcherror if properties object not contain foo.

i can think of 2 ways tackle this. approach 1 is:

myprops getproperty "foo" match {   case v if v != null => dosomethingwith v   case _ => // ignore if foo not exist } 

approach 2 is:

if(myprops containskey "foo") dosomethingwith(myprops getproperty "foo") 

personally, approach 1 better because queries properties once , comment tells non-match intentionally ignored, quite verbose. approach 2 has flaw that, besides querying properties twice, if in near future key changed, has changed @ 2 places here source of bugs.

so, there better way approach 1, shorter, or way done?

try wrapping function in option.

option(myprops getproperty "foo").map {     v => dosomethingwith v } 

option(myprops getproperty "foo") return either some(propertyvalue) or none. if result some(propertyvalue), dosomethingwith (v) in code executed. if none, ignored.

you can have default value in case result none using getorelse function on option.

as mentioned in comments @vladimirmatveev, map not right thing do, if method dosomethingwith has side effects. use foreach instead.