What is the correct syntax for RavenDB Search method in F# -

i trying find posts in ravendb containing word (index there)

here query works, finds starts 'liv'

let post = query {     post in session.query<mytype>()     (post.text.startswith("liv"))     select post } 

an attempt use string.contains() method condition of closure, throw notsupportedexception. here

so trying use search method where:

expression<func<t, object>> fieldselector,  // expression marking field in terms should looked for. 

c# equivalent docs:

list<user> users = session     .query<user>("users/bynameandhobbies")     .search(x => x.name, "adam")     .search(x => x.hobbies, "sport")     .tolist(); 

my first try go with

let x = session.query<mytype>(index).search((fun xe -> xe.text ), "liv") 

but getting error because expects object out. tried downcast string object (what strange idea), getting:

cannot understand how translate x => x.invoke(xe)

at moment, out of ideas. supposed mark field search , return object. ideas?

thank you.

edit 1: expression. gets runtime invalidcastexception because can't cast string obj.

let expr =    <@ func<mytype, _>(fun xe -> xe.text ) @>   |> leafexpressionconverter.quotationtoexpression    |> unbox<system.linq.expressions.expression<func<mytype, _>>> 

you mentioned tried casting string object. tried using :> obj , work.

here working query:

let expr = <@ func<mytype,_>(fun x -> x.text :> obj ) @>                 |> leafexpressionconverter.quotationtoexpression                 |> unbox<linq.expressions.expression<func<mytype,_>>> let events = session.query<mytype>()                 .search(expr, "liv*", decimal 1, searchoptions.or, escapequeryoptions.allowallwildcards)                 |> list.ofseq