From c05570fc4abcfd03f8d5eddb3915725ab50a4474 Mon Sep 17 00:00:00 2001
From: Taras Mychaskiw <taras.mychaskiw@instacart.com>
Date: Thu, 19 Dec 2024 12:56:32 -0500
Subject: [PATCH] =?UTF-8?q?=E2=9A=97=EF=B8=8F=20fiddling=20with=20parsing?=
 =?UTF-8?q?=20util?=
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---
 src/main/scala/org/lemon/advent/lib/parse.scala  | 16 ++++++++++++----
 .../scala/org/lemon/advent/year2024/Day18.scala  |  8 +++++---
 .../scala/org/lemon/advent/year2024/Day19.scala  |  6 ++++--
 3 files changed, 21 insertions(+), 9 deletions(-)

diff --git a/src/main/scala/org/lemon/advent/lib/parse.scala b/src/main/scala/org/lemon/advent/lib/parse.scala
index e80f94d..6064652 100644
--- a/src/main/scala/org/lemon/advent/lib/parse.scala
+++ b/src/main/scala/org/lemon/advent/lib/parse.scala
@@ -1,20 +1,28 @@
 package org.lemon.advent.lib
 
+import scala.math.BigInt
+
 object Chunk:
   def unapplySeq(str: String): Option[Seq[String]] = Some(str.split("\n\n").toSeq)
 
 object Num:
   def unapply[T: Numeric](s: String): Option[T] = summon[Numeric[T]].parseString(s)
 
+// givens for delimiter-separated values to be generic
+given (String => Option[String]) = Some(_)
+given (String => Option[Int]) = Int.unapply
+given (String => Option[Long]) = Long.unapply
+given (String => Option[BigInt]) = BigInt.unapply
+
 object Csv:
   private val delimeter = ","
-  def unapplySeq[T: Numeric](str: String): Option[Seq[T]] = Some(splitParse(str, delimeter).flatMap(Num.unapply[T]))
-  def unapplySeq(str: String): Option[Seq[String]] = Some(splitParse(str, delimeter))
+  def unapplySeq[T](str: String)(using unapply: String => Option[T]): Option[Seq[T]] =
+    Some(splitParse(str, delimeter).flatMap(unapply))
 
 object Wsv:
   private val delimeter = "\\s+"
-  def unapplySeq[T: Numeric](str: String): Option[Seq[T]] = Some(splitParse(str, delimeter).flatMap(Num.unapply[T]))
-  def unapplySeq(str: String): Option[Seq[String]] = Some(splitParse(str, delimeter))
+  def unapplySeq[T](str: String)(using unapply: String => Option[T]): Option[Seq[T]] =
+    Some(splitParse(str, delimeter).flatMap(unapply))
 
 private def splitParse(str: String, delimeter: String): Seq[String] =
   str.split(delimeter).map(_.trim).toSeq
diff --git a/src/main/scala/org/lemon/advent/year2024/Day18.scala b/src/main/scala/org/lemon/advent/year2024/Day18.scala
index 83c7c43..efc6f65 100644
--- a/src/main/scala/org/lemon/advent/year2024/Day18.scala
+++ b/src/main/scala/org/lemon/advent/year2024/Day18.scala
@@ -6,9 +6,11 @@ import org.lemon.advent.lib.graph._
 
 private object Day18:
 
-  def parse(input: String) = input.linesIterator.map(_ match
-    case s"${Csv[Int](x, y)}" => Coord(x, y)
-  ).toSeq
+  def parse(input: String) =
+    import org.lemon.advent.lib.given
+    input.linesIterator.map(_ match
+      case s"${Csv[Int](x, y)}" => Coord(x, y)
+    ).toSeq
 
   def adjacency(area: Area, corrupt: Set[Coord])(coord: Coord): Seq[Coord] =
     coord.adjacent.filterNot(corrupt).filter(area.contains)
diff --git a/src/main/scala/org/lemon/advent/year2024/Day19.scala b/src/main/scala/org/lemon/advent/year2024/Day19.scala
index add417f..0e0f5cb 100644
--- a/src/main/scala/org/lemon/advent/year2024/Day19.scala
+++ b/src/main/scala/org/lemon/advent/year2024/Day19.scala
@@ -6,8 +6,10 @@ import scala.collection.mutable
 
 private object Day19:
 
-  def parse(input: String) = input match
-    case Chunk(towels, targets) => (towels.split(",").map(_.trim).toSeq, targets.linesIterator.toSeq)
+  def parse(input: String) =
+    import org.lemon.advent.lib.given
+    input match
+      case Chunk(Csv[String](towels @ _*), Wsv[String](targets @ _*)) => (towels, targets)
 
   def countLayouts(towels: Seq[String], target: String) =
     val memo = mutable.Map("" -> 1L)