scala: implicit conversion does not work

Question

I have a problem with implicit function, imported from a package.

I have a class that uses Regex to find something in a text. I would like to use it as:

val pattern = "some pattern here".r pattern findSomethingIn some_text

To do so, I define an implicit finction to convert pattern to a wrapper Wrapper that contains findSomethingIn function

package mypackage { class Wrapper ( val pattern: Regex ) { def findSomethingIn( text: String ): Something = ... } object Wrapper { implicit def regex2Something( pat: Regex ): Wrapper = new Wrapper( pat ) } }

if I use it as

import mypackage._ Wrapper.regex2Something( pattern ) findSomethingIn some_text

it works. whereas if i use

pattern findSomethingIn some_text // implicit should work here??

I get

value findPriceIn is not a member of scala.util.amtching.Regex

so the implicit conversion does not work here... What is the problem?

Brian Agnew · Accepted Answer · 2012-08-01 10:28:40Z

You will need

import mypackage.Wrapper._

to import the appropriate methods.

See this blog entry for more info, and note in particular the definition/import of the Conversions object.

Nick H · Accepted Answer · 2012-08-02 12:01:12Z

Brian's answer is best, though an alternative would be to use a package object

package object mypackage { implicit def regex2Something( pat: Regex ): Wrapper = new Wrapper( pat ) }

This will allow you to use your original import mypackage._ line, as the implicit def will be in the package itself.

http://www.scala-lang.org/docu/files/packageobjects/packageobjects.html

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