parser combinator, json parser, future, other shit

2024-04-02 15:47:10 +02:00
parent 1feb3ca2a7
commit 54dde5f1f7
10 changed files with 439 additions and 2 deletions
--- a/src/main/kotlin/blitz/parse/JSON.kt
+++ b/src/main/kotlin/blitz/parse/JSON.kt
@@ -0,0 +1,80 @@
+package blitz.parse
+
+import blitz.parse.comb.*
+
+object JSON {
+    lateinit var jsonElement: Parser<Element>
+    val jsonNum = parser {
+        it.map(NumParse.float)?.mapSecond { n ->
+            Number(n)
+        }
+    }
+    val jsonString = parser {
+        it.require("\"")
+            ?.untilRequire("\"") { str -> Str(str) }
+    }
+    val jsonArray = parser {
+        it.require("[")
+            ?.array(",") { elem ->
+                elem.whitespaces()
+                    .map(jsonElement)
+                    ?.whitespaces()
+            }
+            ?.require("]")
+            ?.mapSecond { x -> Array(x) }
+    }
+    val jsonObj = parser {
+        it.require("{")
+            ?.array(",") { elem ->
+                elem.whitespaces()
+                    .map(jsonString)
+                    ?.mapSecond { it.str }
+                    ?.whitespaces()
+                    ?.require(":")
+                    ?.whitespaces()
+                    ?.map(jsonElement)
+                    ?.whitespaces()
+            }
+            ?.require("}")
+            ?.mapSecond { x -> Obj(x.toMap()) }
+    }
+
+    init {
+        jsonElement = (jsonArray or jsonNum or jsonString or jsonObj).trim()
+    }
+
+    interface Element {
+        val arr get() = (this as Array).value
+        val num get() = (this as Number).value
+        val str get() = (this as Str).value
+        val obj get() = (this as Obj).value
+
+        fun isArr() = this is Array
+        fun isNum() = this is Number
+        fun isStr() = this is Str
+        fun isObj() = this is Obj
+    }
+
+    data class Array(val value: List<Element>): Element {
+        override fun toString(): String =
+            value.joinToString(separator = ", ", prefix = "[", postfix = "]")
+    }
+
+    data class Number(val value: Double): Element {
+        override fun toString(): String =
+            value.toString()
+    }
+
+    data class Str(val value: String): Element {
+        override fun toString(): String =
+            "\"$value\""
+    }
+
+    data class Obj(val value: Map<String, Element>): Element {
+        override fun toString(): String =
+            value.map { (k, v) -> "\"$k\": $v" }.joinToString(separator = ", ", prefix = "{", postfix = "}")
+    }
+
+    fun parse(string: String): Element? =
+        jsonElement(Parsable(string))?.second
+}