multiline string literals

docs/samples/сумма_ряда.lyng.md

@@ -48,6 +48,7 @@ $$ \ln(1+x)=x-{\dfrac {x^{2}}{2}}+{\dfrac {x^{3}}{3}}-\cdots =\sum \limits _{n=0
     }
     assert( почти_равны( 0.0005, 0.000501 ) )
 
-Во многих случаях вычисление $n+1$ члена значительно проще cчитается от предыдущего члена, в нашем случае это можно было бы записать через итератор, что мы вскоре добавим.
+Во многих случаях вычисление $n+1$ члена значительно проще cчитается от предыдущего члена, в нашем случае это можно было бы записать через итератор, см [Iterable] и `flow` в [parallelism].
 
-(продолжение следует)
+[Iterable]: ../Iterable.md
+[parallelism]: ../parallelism.md

docs/tutorial.md

@@ -1259,7 +1259,19 @@ String literal could be multiline:
     "Hello
     World"
 
-though multiline literals is yet work in progress.
+In this case, it will be passed literally ot "hello\n    World". But, if there are
+several lines with common left indent, it will be removed, also, forst and last lines,
+if blank, will be removed too, for example:
+
+    println("
+            This is a multiline text.
+            This is a second line.
+        ")
+    >>> This is a multiline text.
+    >>> This is a second line.
+    >>> void
+
+- as expected, empty lines and common indent were removed. It is much like kotlin's `""" ... """.trimIndent()` technique, but simpler ;)
 
 # Built-in functions
 

lynglib/build.gradle.kts

@@ -4,7 +4,7 @@ import org.jetbrains.kotlin.gradle.ExperimentalWasmDsl
 import org.jetbrains.kotlin.gradle.dsl.JvmTarget
 
 group = "net.sergeych"
-version = "0.8.4-SNAPSHOT"
+version = "0.8.5-SNAPSHOT"
 
 buildscript {
     repositories {

lynglib/src/commonMain/kotlin/net/sergeych/lyng/Parser.kt

@@ -375,6 +375,32 @@ private class Parser(fromPos: Pos) {
 
     private val currentChar: Char get() = pos.currentChar
 
+    private fun fixMultilineStringLiteral(source: String): String {
+        val sizes = mutableListOf<Int>()
+        val lines = source.lines().toMutableList()
+        if( lines.size == 0 ) return ""
+        if( lines[0].isBlank() ) lines.removeFirst()
+        if( lines.isEmpty()) return ""
+        if( lines.last().isBlank() ) lines.removeLast()
+
+        val normalized = lines.map { l ->
+            if( l.isBlank() ) {
+                sizes.add(-1)
+                ""
+            }
+            else {
+                val margin = leftMargin(l)
+                sizes += margin
+                " ".repeat(margin) + l.trim()
+            }
+        }
+        val commonMargin = sizes.filter { it >= 0 }.min()
+        val fixed = if( commonMargin < 1 ) lines else normalized.map {
+            if( it.isBlank() ) "" else it.drop(commonMargin)
+        }
+        return fixed.joinToString("\n")
+    }
+
     private fun loadStringToken(): Token {
         val start = currentPos
 
@@ -383,6 +409,7 @@ private class Parser(fromPos: Pos) {
 //        start = start.back()
 
         val sb = StringBuilder()
+        var newlineDetected = false
         while (currentChar != '"') {
             if (pos.end) throw ScriptError(start, "unterminated string started there")
             when (currentChar) {
@@ -397,6 +424,12 @@ private class Parser(fromPos: Pos) {
                     }
                 }
 
+                '\n', '\r'-> {
+                    newlineDetected = true
+                    sb.append(currentChar)
+                    pos.advance()
+                }
+
                 else -> {
                     sb.append(currentChar)
                     pos.advance()
@@ -404,7 +437,10 @@ private class Parser(fromPos: Pos) {
             }
         }
         pos.advance()
-        return Token(sb.toString(), start, Token.Type.STRING)
+
+        val result = sb.toString().let { if( newlineDetected ) fixMultilineStringLiteral(it) else it }
+
+        return Token(result, start, Token.Type.STRING)
     }
 
     /**

lynglib/src/commonMain/kotlin/net/sergeych/lyng/text_tools.kt

@@ -0,0 +1,13 @@
+package net.sergeych.lyng
+
+fun leftMargin(s: String): Int {
+    var cnt = 0
+    for (c in s) {
+        when (c) {
+            ' ' -> cnt++
+            '\t' -> cnt = (cnt / 4.0 + 0.9).toInt() * 4
+            else -> break
+        }
+    }
+    return cnt
+}

lynglib/src/commonTest/kotlin/ScriptTest.kt

@@ -2794,4 +2794,45 @@ class ScriptTest {
         println(y.list)
     }
 
+    @Test
+    fun testMultilineStrings() = runTest {
+        assertEquals(
+            """
+            This is a multiline text.
+            This is a second line.
+        """.trimIndent(), eval(
+                """
+            "
+                This is a multiline text.
+                This is a second line.
+            "
+        """.trimIndent()
+            ).toString()
+        )
+        assertEquals(
+            """
+            This is a multiline text.
+        """.trimIndent(), eval(
+                """
+            "
+                This is a multiline text.
+            "
+        """.trimIndent()
+            ).toString()
+        )
+        assertEquals(
+            """
+
+            This is a multiline text.
+        """.trimIndent(), eval(
+                """
+            "
+
+                This is a multiline text.
+            "
+        """.trimIndent()
+            ).toString()
+        )
+    }
+
 }

lynglib/src/jvmTest/kotlin/BookTest.kt

@@ -6,6 +6,7 @@ import kotlinx.coroutines.runBlocking
 import kotlinx.coroutines.test.runTest
 import net.sergeych.lyng.Scope
 import net.sergeych.lyng.Script
+import net.sergeych.lyng.leftMargin
 import net.sergeych.lyng.obj.ObjVoid
 import java.nio.file.Files
 import java.nio.file.Files.readAllLines
@@ -16,18 +17,6 @@ import kotlin.test.Test
 import kotlin.test.assertEquals
 import kotlin.test.fail
 
-fun leftMargin(s: String): Int {
-    var cnt = 0
-    for (c in s) {
-        when (c) {
-            ' ' -> cnt++
-            '\t' -> cnt = (cnt / 4.0 + 0.9).toInt() * 4
-            else -> break
-        }
-    }
-    return cnt
-}
-
 data class DocTest(
     val fileName: String,
     val line: Int,

settings.gradle.kts

@@ -13,7 +13,6 @@ dependencyResolutionManagement {
         maven("https://maven.universablockchain.com/")
         maven("https://gitea.sergeych.net/api/packages/SergeychWorks/maven")
         mavenLocal()
-        maven("https://gitea.sergeych.net/api/packages/SergeychWorks/maven")
     }
 }