Provide comparison operators for supported data types

[mxl]

Version: 1.0.2-SNAPSHOT

E. g. for java.util.Date:

trait Operators {
  this: SqlContext[_, _] =>
  implicit class DateComparison(left: Date) {
    def >(right: Date) = quote(infix"$left > $right".as[Boolean])

    def <(right: Date) = quote(infix"$left < $right".as[Boolean])

    def >=(right: Date) = quote(infix"$left >= $right".as[Boolean])

    def <=(right: Date) = quote(infix"$left <= $right".as[Boolean])
  }
}

val ctx = new MirrorContext[MirrorSqlDialect,SnakeCase] with Operators

Also:

• string
• UUID
• org.joda.time types

@getquill/maintainers WDYT?

[fwbrasil]

@mxl is this fixed by #678

[mxl]

@fwbrasil Sorry for late response 😄 No, #678 is just documentation update, but I want to integrate this in Quill.

[fwbrasil]

@mxl sounds good

[mosyp]

@mxl What if we could introduce some new dsl, something like this

trait ComparisonOperatorsDsl {
  this: Context[_, _] =>
  trait ComparisonOperators[T] {
    def left: T
    def >(right: T) = quote(infix"$left > $right".as[Boolean])
      ...
  }

  implicit class StringComparison(left: String) extends ComparisonOperators[String]
}

trait SqlComparisonOperators {
  this: SqlContext[_, _] =>

  implicit class DateComparison(left: Date) extends ComparisonOperators[Date]
  implicit class ContextSpecificComparison(left: ContextSpecific) extends ComparisonOperators[ContextSpecific]
}

[mxl]

@mentegy Cool! 👍

[mxl]

Also it would be nice to provide other operators, for example, string concatenation:

implicit class StringConcatenation(left: String) {
   def +(right: String) = quote(infix"CONCAT($left, $right)".as[String])
}

I suggest to change title and description of this issue and not create another one.
WDYT @getquill/maintainers?

[mosyp]

@mxl for string concat we can just enhance this class https://github.com/getquill/quill/blob/master/quill-sql/src/main/scala/io/getquill/context/sql/dsl/SqlDsl.scala#L8-L10, since it only applicable for sql. But this issue leave only for comparisons

[mosyp]

also i'm not sure that + will work for strings since default method from scala will take a place first. Changes to parsing ast required

[mxl]

@mentegy Ok!

[deusaquilus]

For things like Date comparison, I'd like to have operators that I can use both inside-of and outside-of Quill contexts. Otherwise my coworkers are going to try to use these wonderful > and < operators outside of quoted contexts and lots of WTFs will result. I'd like something like this:

implicit class DateOps(d:java.util.Date /* Or LocalDateTime etc...*/ ) {
  def >(o:java.util.Date /* Or LocalDateTime etc...*/):Boolean = d.getTime > o.getTime
  def <(o:java.util.Date /* Or LocalDateTime etc...*/):Boolean = d.getTime < o.getTime
  // etc...
}

Then have Parsing.scala figure this all out e.g:

val dateContextParser: Parser[Ast] = Parser[Ast] {
  case q"$pack.DateOps($d).>($o) =>
    BinaryOperation(astParser(d), NumericOperator.`>`, astParser(o))
  // etc...
}

Then people can use these operators both inside and outside of Quill contexts:

// It works here:
val q = quote {
  query[Record].filter(_.createdAt > lift(runtimeDateValue))
}
// It also works here:
val r:Record = ...
if (r.createdAt > runtimeDateValue) doSomething()

WDYT? @mentegy @mxl @fwbrasil

[slgobinath]

Hi, Any updates on this feature? I am looking for a way to compare String using quill. I tried to extend quill using infix function as shown below (code from #862 ), but the operators are conflicting with the default Scala comparison operators.

implicit class StringOperators(left: String) {
  def >(right: String) = quote(infix"STRCMP($left, $right) > 0".as[Boolean])
}

If I change > to something like >> or >>>, it works but looks odd.