add VarText utils

.editorconfig

@@ -11,7 +11,7 @@ ij_formatter_off_tag = @formatter:off
 ij_formatter_on_tag = @formatter:on
 ij_formatter_tags_enabled = true
 ij_smart_tabs = false
-ij_visual_guides = 
+ij_visual_guides = 95
 ij_wrap_on_typing = false
 
 [*.conf]
@@ -528,7 +528,7 @@ ij_scala_preserve_space_after_method_declaration_name = false
 ij_scala_reformat_on_compile = false
 ij_scala_replace_case_arrow_with_unicode_char = false
 ij_scala_replace_for_generator_arrow_with_unicode_char = false
-ij_scala_replace_lambda_with_greek_letter = false
+ij_scala_replace_lambda_with_greek_letter = true
 ij_scala_replace_map_arrow_with_unicode_char = false
 ij_scala_scalafmt_config_path = 
 ij_scala_scalafmt_fallback_to_default_settings = false
@@ -847,6 +847,7 @@ ij_typescript_union_types_wrap = on_every_item
 ij_typescript_use_chained_calls_group_indents = false
 ij_typescript_use_double_quotes = true
 ij_typescript_use_explicit_js_extension = auto
+ij_typescript_use_import_type = auto
 ij_typescript_use_path_mapping = always
 ij_typescript_use_public_modifier = false
 ij_typescript_use_semicolon_after_statement = true
@@ -1026,6 +1027,7 @@ ij_javascript_union_types_wrap = on_every_item
 ij_javascript_use_chained_calls_group_indents = false
 ij_javascript_use_double_quotes = false
 ij_javascript_use_explicit_js_extension = auto
+ij_javascript_use_import_type = auto
 ij_javascript_use_path_mapping = always
 ij_javascript_use_public_modifier = false
 ij_javascript_use_semicolon_after_statement = false
@@ -1319,7 +1321,7 @@ ij_kotlin_wrap_elvis_expressions = 1
 ij_kotlin_wrap_expression_body_functions = 1
 ij_kotlin_wrap_first_method_in_call_chain = false
 
-[{*.har,*.jsb2,*.jsb3,*.json,.babelrc,.conf,.eslintrc,.prettierrc,.stylelintrc,bowerrc,jest.config,mcmod.info,meatball_from_mutton.json,pack.mcmeta}]
+[{*.har,*.jsb2,*.jsb3,*.json,*.jsonc,*.postman_collection,*.postman_collection.json,*.postman_environment,*.postman_environment.json,.babelrc,.conf,.eslintrc,.prettierrc,.stylelintrc,bowerrc,jest.config,mcmod.info,meatball_from_mutton.json,pack.mcmeta}]
 ij_smart_tabs = true
 ij_json_array_wrapping = split_into_lines
 ij_json_keep_blank_lines_in_code = 0
@@ -1401,7 +1403,7 @@ ij_markdown_min_lines_between_paragraphs = 1
 ij_markdown_wrap_text_if_long = true
 ij_markdown_wrap_text_inside_blockquotes = true
 
-[{*.pb,*.textproto}]
+[{*.pb,*.textproto,*.txtpb}]
 indent_size = 2
 indent_style = space
 tab_width = 2

src/main/scala/cc/sukazyo/cono/morny/core/MornyCoeur.scala

@@ -13,6 +13,7 @@ import cc.sukazyo.cono.morny.util.schedule.Scheduler
 import cc.sukazyo.cono.morny.util.EpochDateTime.EpochMillis
 import cc.sukazyo.cono.morny.util.time.WatchDog
 import cc.sukazyo.cono.morny.util.GivenContext
+import cc.sukazyo.cono.morny.util.UseString.MString
 import cc.sukazyo.cono.morny.util.UseThrowable.toLogString
 import com.pengrad.telegrambot.TelegramBot
 import com.pengrad.telegrambot.request.GetMe
@@ -119,12 +120,12 @@ class MornyCoeur (modules: List[MornyModule])(using val config: MornyConfig)(tes
 	val externalContext: GivenContext = GivenContext()
 	import cc.sukazyo.cono.morny.util.dataview.Table.format as fmtTable
 	logger `info`
-		s"""The following Modules have been added to current Morny:
+		m"""The following Modules have been added to current Morny:
 		   |${fmtTable(
-				("Module ID" :: "Module Name" :: "Module Version" :: Nil)::Nil :::
+			"Module ID" :: "Module Name" :: "Module Version" :: Nil,
-				modules.map(f => f.id :: f.name :: f.version :: Nil)
+			modules.map(f => f.id :: f.name :: f.version :: Nil)*
-			).replaceAll("\n", "\n|")}
+		)}
-		   |""".stripMargin
+		   |"""
 	
 	///>>> BLOCK START instance configure & startup stage 1
 	

src/main/scala/cc/sukazyo/cono/morny/core/bot/command/MornyInformation.scala

@@ -3,6 +3,7 @@ package cc.sukazyo.cono.morny.core.bot.command
 import cc.sukazyo.cono.morny.core.{MornyCoeur, MornySystem}
 import cc.sukazyo.cono.morny.core.bot.api.{ICommandAlias, ITelegramCommand}
 import cc.sukazyo.cono.morny.core.bot.api.messages.{ErrorMessage, MessagingContext}
+import cc.sukazyo.cono.morny.core.Log.logger
 import cc.sukazyo.cono.morny.data.MornyInformation.*
 import cc.sukazyo.cono.morny.data.TelegramStickers
 import cc.sukazyo.cono.morny.reporter.MornyReport
@@ -10,13 +11,14 @@ import cc.sukazyo.cono.morny.util.CommonFormat.{formatDate, formatDuration}
 import cc.sukazyo.cono.morny.util.tgapi.formatting.TelegramParseEscape.escapeHtml as h
 import cc.sukazyo.cono.morny.util.tgapi.InputCommand
 import cc.sukazyo.cono.morny.util.tgapi.TelegramExtensions.Requests.unsafeExecute
+import cc.sukazyo.cono.morny.util.var_text
+import cc.sukazyo.cono.morny.util.var_text.VarText
 import com.pengrad.telegrambot.model.Update
 import com.pengrad.telegrambot.model.request.ParseMode
 import com.pengrad.telegrambot.request.{SendMessage, SendPhoto, SendSticker}
 import com.pengrad.telegrambot.TelegramBot
 
 import java.lang.System
-// todo: maybe move some utils method outside
 class MornyInformation (using coeur: MornyCoeur) extends ITelegramCommand {
 	private given TelegramBot = coeur.account
 	
@@ -74,11 +76,19 @@ class MornyInformation (using coeur: MornyCoeur) extends ITelegramCommand {
 			cxt.bind_chat.id,
 			getAboutPic
 		).caption(
-			s"""<b>Morny Cono</b>
+			// language=html
+			(VarText(
+				"""<b>Morny Cono</b>
 				  |来自安妮的侍从小鼠。
 				  |————————————————
-			   |$getMornyAboutLinksHTML"""
+				  |{about_links}""".stripMargin
-					.stripMargin
+			).render(
+				"about_links" -> getMornyAboutLinksHTML
+			) :: Nil)
+				.map( f =>
+					logger `trace` f
+					f
+				).head
 		).parseMode(ParseMode HTML).replyToMessageId(cxt.bind_message.messageId)
 			.unsafeExecute
 		
@@ -127,16 +137,26 @@ class MornyInformation (using coeur: MornyCoeur) extends ITelegramCommand {
 		val versionGitHTML = if (MornySystem.GIT_COMMIT nonEmpty) s"git $getVersionGitTagHTML" else ""
 		SendMessage(
 			event.message.chat.id,
+			VarText(
 				// language=html
-			s"""version:
+				"""version:
-			   |- Morny <code>${h(MornySystem.CODENAME toUpperCase)}</code>
+				  |- Morny <code>{version_codename}</code>
-			   |- <code>${h(MornySystem.VERSION_BASE)}</code>$versionDeltaHTML${if (MornySystem.GIT_COMMIT nonEmpty) "\n- " + versionGitHTML else ""}
+				  |- <code>{version_base}</code>{version_delta_html}{version_git_suffix}
 				  |coeur md5_hash:
-			   |- <code>${h(MornySystem.getJarMD5)}</code>
+				  |- <code>{md5}</code>
 				  |coding timestamp:
-			   |- <code>${MornySystem.CODE_TIMESTAMP}</code>
+				  |- <code>{time_millis}</code>
-			   |- <code>${h(formatDate(MornySystem.CODE_TIMESTAMP, 0))} [UTC]</code>
+				  |- <code>{time_utc} [UTC]</code>
 				  |""".stripMargin
+			).render(
+				"version_codename" -> h(MornySystem.CODENAME.toUpperCase),
+				"version_base" -> h(MornySystem.VERSION_BASE),
+				"version_delta_html" -> versionDeltaHTML,
+				"version_git_suffix" -> (if (MornySystem.GIT_COMMIT nonEmpty) "\n- " + versionGitHTML else ""),
+				"md5" -> h(MornySystem.getJarMD5),
+				"time_millis" -> MornySystem.CODE_TIMESTAMP,
+				"time_utc" -> h(formatDate(MornySystem.CODE_TIMESTAMP, 0)),
+			)
 		).replyToMessageId(event.message.messageId).parseMode(ParseMode HTML)
 			.unsafeExecute
 	}
@@ -145,27 +165,48 @@ class MornyInformation (using coeur: MornyCoeur) extends ITelegramCommand {
 		def sysprop (p: String): String = System.getProperty(p)
 		SendMessage(
 			event.message.chat.id,
+			VarText(
 				/* language=html */
-			s"""system:
+				"""system:
-			   |- <code>${h(if getRuntimeHostname nonEmpty then getRuntimeHostname.get else "<unknown-host>")}</code>
+				  |- <code>{hostname}</code>
-			   |- <code>${h(sysprop("os.name"))}</code> <code>${h(sysprop("os.arch"))}</code> <code>${h(sysprop("os.version"))}</code>
+				  |- <code>{os.name}</code> <code>{os.arch}</code> <code>{os.version}</code>
 				  |java runtime:
-			   |- <code>${h(sysprop("java.vm.vendor"))}.${h(sysprop("java.vm.name"))}</code>
+				  |- <code>{java.vm.vendor}.{java.vm.name}</code>
-			   |- <code>${h(sysprop("java.vm.version"))}</code>
+				  |- <code>{java.vm.version}</code>
 				  |vm memory:
-			   |- <code>${Runtime.getRuntime.totalMemory/1024/1024}</code> / <code>${Runtime.getRuntime.maxMemory/1024/1024}</code> MB
+				  |- <code>{memory_used_mb}</code> / <code>{memory_available_mb}</code> MB
-			   |- <code>${Runtime.getRuntime.availableProcessors}</code> cores
+				  |- <code>{cpu_cores}</code> cores
 				  |coeur version:
-			   |- $getVersionAllFullTagHTML
+				  |- {version_full}
-			   |- <code>${h(MornySystem.getJarMD5)}</code>
+				  |- <code>{coeur_md5}</code>
-			   |- <code>${h(formatDate(MornySystem.CODE_TIMESTAMP, 0))} [UTC]</code>
+				  |- <code>{compile_time_utc} [UTC]</code>
-			   |- [<code>${MornySystem.CODE_TIMESTAMP}</code>]
+				  |- [<code>{compile_time_millis}</code>]
 				  |continuous:
-			   |- <code>${h(formatDuration(System.currentTimeMillis - coeur.coeurStartTimestamp))}</code>
+				  |- <code>{running_duration}</code>
-			   |- [<code>${System.currentTimeMillis - coeur.coeurStartTimestamp}</code>]
+				  |- [<code>{running_duration_ms}</code>]
-			   |- <code>${h(formatDate(coeur.coeurStartTimestamp, 0))}</code>
+				  |- <code>{startup_time_utc}</code>
-			   |- [<code>${coeur.coeurStartTimestamp}</code>]"""
+				  |- [<code>{startup_time_millis}</code>]"""
 					.stripMargin
+			).render(
+				"hostname" -> h(if getRuntimeHostname nonEmpty then getRuntimeHostname.get else "<unknown-host>"),
+				"os.name" -> h(sysprop("os.name")),
+				"os.arch" -> h(sysprop("os.arch")),
+				"os.version" -> h(sysprop("os.version")),
+				"java.vm.vendor" -> h(sysprop("java.vm.vendor")),
+				"java.vm.name" -> h(sysprop("java.vm.name")),
+				"java.vm.version" -> h(sysprop("java.vm.version")),
+				"memory_used_mb" -> (Runtime.getRuntime.totalMemory/1024/1024),
+				"memory_available_mb" -> (Runtime.getRuntime.maxMemory/1024/1024),
+				"cpu_cores" -> Runtime.getRuntime.availableProcessors,
+				"version_full" -> getVersionAllFullTagHTML,
+				"coeur_md5" -> h(MornySystem.getJarMD5),
+				"compile_time_utc" -> h(formatDate(MornySystem.CODE_TIMESTAMP, 0)),
+				"compile_time_millis" -> MornySystem.CODE_TIMESTAMP,
+				"running_duration" -> h(formatDuration(System.currentTimeMillis - coeur.coeurStartTimestamp)),
+				"running_duration_ms" -> (System.currentTimeMillis - coeur.coeurStartTimestamp),
+				"startup_time_utc" -> h(formatDate(coeur.coeurStartTimestamp, 0)),
+				"startup_time_millis" -> coeur.coeurStartTimestamp
+			)
 		).parseMode(ParseMode HTML).replyToMessageId(event.message.messageId)
 			.unsafeExecute
 	}
@@ -174,12 +215,18 @@ class MornyInformation (using coeur: MornyCoeur) extends ITelegramCommand {
 //		if !coeur.trusted.isTrusted(update.message.from.id) then return;
 		SendMessage(
 			update.message.chat.id,
+			VarText(
 				// language=html
-			s"""<b>Coeur Task Scheduler:</b>
+				"""<b>Coeur Task Scheduler:</b>
-			   | - <i>scheduled tasks</i>: <code>${coeur.tasks.amount}</code>
+				  | - <i>scheduled tasks</i>: <code>{coeur.tasks.amount}</code>
-			   | - <i>scheduler status</i>: <code>${coeur.tasks.state}</code>
+				  | - <i>scheduler status</i>: <code>{coeur.tasks.state}</code>
-			   | - <i>current runner status</i>: <code>${coeur.tasks.runnerState}</code>
+				  | - <i>current runner status</i>: <code>{coeur.tasks.runnerState}</code>
 				  |""".stripMargin
+			).render(
+				"coeur.tasks.amount" -> coeur.tasks.amount,
+				"coeur.tasks.state" -> coeur.tasks.state,
+				"coeur.tasks.runnerState" -> coeur.tasks.runnerState
+			)
 		).parseMode(ParseMode.HTML).replyToMessageId(update.message.messageId)
 			.unsafeExecute
 	}
@@ -188,10 +235,14 @@ class MornyInformation (using coeur: MornyCoeur) extends ITelegramCommand {
 		coeur.externalContext >> { (reporter: MornyReport) =>
 			SendMessage(
 				update.message.chat.id,
+				VarText(
 					// language=html
-				s"""<b>Event Statistics :</b>
+					"""<b>Event Statistics :</b>
 					  |in today
-				   |${reporter.EventStatistics.eventStatisticsHTML}""".stripMargin
+					  |{event_statistics}""".stripMargin
+				).render(
+					"event_statistics" -> reporter.EventStatistics.eventStatisticsHTML
+				)
 			).parseMode(ParseMode.HTML).replyToMessageId(update.message.messageId)
 				.unsafeExecute
 		} || {

src/main/scala/cc/sukazyo/cono/morny/data/MornyInformation.scala

@@ -1,6 +1,7 @@
 package cc.sukazyo.cono.morny.data
 
 import cc.sukazyo.cono.morny.core.{MornyAbout, MornySystem}
+import cc.sukazyo.cono.morny.util.var_text.VarText
 
 import java.net.InetAddress
 import java.rmi.UnknownHostException
@@ -39,9 +40,16 @@ object MornyInformation {
 	def getAboutPic: Array[Byte] = TelegramImages.IMG_ABOUT get
 	
 	def getMornyAboutLinksHTML: String =
-		s"""<a href='${MornyAbout MORNY_SOURCECODE_LINK}'>source code</a> | <a href='${MornyAbout MORNY_SOURCECODE_SELF_HOSTED_MIRROR_LINK}'>backup</a>
+		VarText(
-		   |<a href='${MornyAbout MORNY_ISSUE_TRACKER_LINK}'>反馈 / issue tracker</a>
+			// language=html
-		   |<a href='${MornyAbout MORNY_USER_GUIDE_LINK}'>使用说明书 / user guide & docs</a>"""
+			"""<a href='{MORNY_SOURCECODE_LINK}'>source code</a> | <a href='{MORNY_SOURCECODE_SELF_HOSTED_MIRROR_LINK}'>backup</a>
-			.stripMargin
+			  |<a href='{MORNY_ISSUE_TRACKER_LINK}'>反馈 / issue tracker</a>
+			  |<a href='{MORNY_USER_GUIDE_LINK}'>使用说明书 / user guide & docs</a>""".stripMargin
+		).render(
+			"MORNY_SOURCECODE_LINK" -> MornyAbout.MORNY_SOURCECODE_LINK,
+			"MORNY_SOURCECODE_SELF_HOSTED_MIRROR_LINK" -> MornyAbout.MORNY_SOURCECODE_SELF_HOSTED_MIRROR_LINK,
+			"MORNY_ISSUE_TRACKER_LINK" -> MornyAbout.MORNY_ISSUE_TRACKER_LINK,
+			"MORNY_USER_GUIDE_LINK" -> MornyAbout.MORNY_USER_GUIDE_LINK
+		)
 	
 }

src/main/scala/cc/sukazyo/cono/morny/util/CommonFormat.scala

@@ -65,7 +65,7 @@ object CommonFormat {
 	
 	/** human readable [[String]] that describes the millis duration.
 	  *
-	  * {{{
+	  * @example {{{
 	  *	    scala> formatDuration(10)
 	  *	    val res0: String = 10ms
 	  *

src/main/scala/cc/sukazyo/cono/morny/util/ConvertByteHex.scala

@@ -9,7 +9,10 @@ package cc.sukazyo.cono.morny.util
   * for example, byte `0` is binary `0000 0000`, it will be converted to
   * `"00"`, and the byte `-1` is binary `1111 1111` which corresponding
   * `"ff"`.
-  * {{{
+  *
+  * while converting byte array, the order is: the 1st element of the array
+  * will be put most forward, then the following added to the tail of hex string.
+  * @example {{{
   *     scala> 0.toByte.toHex
   *     val res6: String = 00
   *
@@ -18,11 +21,7 @@ package cc.sukazyo.cono.morny.util
   *
   *     scala> -1.toByte.toHex
   *     val res7: String = ff
-  * }}}
   *     
-  * while converting byte array, the order is: the 1st element of the array
-  * will be put most forward, then the following added to the tail of hex string.
-  * {{{
   *     scala> Array[Byte](0, 1, 2, 3).toHex
   *     val res5: String = 00010203
   * }}}

src/main/scala/cc/sukazyo/cono/morny/util/GivenContext.scala

@@ -23,8 +23,7 @@ object GivenContext {
 
 /** A mutable collection that can store(provide) any typed value and read(use/consume) that value by type.
   *
-  * ## Simple Guide
+  * @example {{{
-  * {{{
   *     val cxt = GivenContext()
   *     class BaseClass {}
   *     class MyImplementation extends BaseClass {}

src/main/scala/cc/sukazyo/cono/morny/util/StringEnsure.scala

@@ -2,7 +2,6 @@ package cc.sukazyo.cono.morny.util
 
 object StringEnsure {
 	
-	
 	extension (str: String) {
 		
 		/** Ensure the string have a length not smaller that the given length.
@@ -36,8 +35,8 @@ object StringEnsure {
 		  * Notice that this method have un-defined behavior when the length of the String is less than
 		  * the character that will be kept, so change the character length that will be kept in your need.
 		  *
-		  * Examples:
+		  * 
-		  * {{{
+		  * @example {{{
 		  *     scala> val someUserToken = "TOKEN_UV:V927c092FV$REFV[p':V<IE#*&@()U8eR)c"
 		  *     val someUserToken: String = TOKEN_UV:V927c092FV$REFV[p':V<IE#*&@()U8eR)c
 		  *

src/main/scala/cc/sukazyo/cono/morny/util/UseString.scala

@@ -0,0 +1,108 @@
+package cc.sukazyo.cono.morny.util
+
+object UseString {
+	
+	/** Convert a list of [[String]] to a multiline string.
+	  *
+	  * Each input string will be a line in the new string, and the the string
+	  * that equals to `null` will be ignored.
+	  * 
+	  * @example {{{
+	  * scala> println(MString(
+	  *      "line1", // line 1
+	  *      "line2", // line 2
+	  *      "",      // line 3
+	  *      null,    // will be ignored
+	  *      "line4", // line 4
+	  *  ))
+	  * line1
+	  * line2
+	  *
+	  * line4
+	  * }}}
+	  * 
+	  * @since 2.0.0
+	  */
+	def MString (lines: String*): String =
+		lines.filterNot(_ == null).mkString("\n")
+	
+	/** A simple string interpolator implementation that fixed [[scala.collection.immutable.StringOps.stripMargin]]
+	  * will remove the interpolated string's `|` when using s"" or f"" at the
+	  * same time.
+	  *
+	  * @see [[m]]
+	  */
+	implicit class MString (private val sc: StringContext) extends AnyVal:
+		/** A simple string interpolator implementation that fixed [[scala.collection.immutable.StringOps.stripMargin]]
+		  * will remove the interpolated string's `|` when using s"" or f"" at
+		  * the same time.
+		  *
+		  * It will process stripMargin for each raw texts, then do the s""
+		  * interpolation. So, the interpolated string's margin character (`|`)
+		  * will be kept.
+		  *
+		  * This should be useful when inserting a ascii table or ascii art when
+		  * using string interpolator.
+		  *
+		  * @example {{{
+		  * scala> val table =
+		  *      raw""" +--------+
+		  *           | |  head  |
+		  *           | +--------+
+		  *           | |  body  |
+		  *           | |  next  |
+		  *           | +--------+
+		  *           |""".stripMargin
+		  *
+		  * val table: String = " +--------+
+		  *  |  head  |
+		  *  +--------+
+		  *  |  body  |
+		  *  |  next  |
+		  *  +--------+
+		  * "
+		  *
+		  * scala> println(table)
+		  *  +--------+
+		  *  |  head  |
+		  *  +--------+
+		  *  |  body  |
+		  *  |  next  |
+		  *  +--------+
+		  *
+		  *
+		  * scala> println(
+		  *      s"""Here is a table:
+		  *         |$table
+		  *         |""".stripMargin)
+		  * Here is a table:
+		  *  +--------+
+		  *   head  |
+		  *  +--------+
+		  *   body  |
+		  *   next  |
+		  *  +--------+
+		  *
+		  *
+		  *
+		  * scala> println(
+		  *      m"""Here is a table:
+		  *         |$table
+		  *         |""")
+		  * Here is a table:
+		  *  +--------+
+		  *  |  head  |
+		  *  +--------+
+		  *  |  body  |
+		  *  |  next  |
+		  *  +--------+
+		  * }}}
+		  *
+		  * @since 2.0.0
+		  */
+		def m (args: Any*): String = {
+			StringContext(sc.parts.map(_.stripMargin)*)
+				.s(args*)
+		}
+	
+}

src/main/scala/cc/sukazyo/cono/morny/util/dataview/Table.scala

@@ -2,7 +2,8 @@ package cc.sukazyo.cono.morny.util.dataview
 
 object Table {
 	
-	def format (table: Seq[Seq[Any]]): String = {
+	def format (title: Seq[Any], data: Seq[Any]*): String = {
+		val table = data.prepended(title)
 		if (table.isEmpty) ""
 		else {
 			// Get column widths based on the maximum cell width in each column (+2 for a one character padding on each side)

src/main/scala/cc/sukazyo/cono/morny/util/schedule/Task.scala

@@ -38,8 +38,7 @@ trait Task extends Ordered[Task] {
 	
 	/** Returns this task's object name and the task name.
 	  *
-	  * for example:
+	  * @example {{{
-	  * {{{
 	  *     scala> val task = new Task {
 	  *         val name = "example-task"
 	  *         val scheduledTimeMillis = 0

src/main/scala/cc/sukazyo/cono/morny/util/var_text/VTNode.scala

@@ -0,0 +1,9 @@
+package cc.sukazyo.cono.morny.util.var_text
+
+trait VTNode {
+	
+	def render (vars: Map[String, String]): String
+	
+	def serialize: String
+	
+}

src/main/scala/cc/sukazyo/cono/morny/util/var_text/VTNodeLiteral.scala

@@ -0,0 +1,23 @@
+package cc.sukazyo.cono.morny.util.var_text
+
+case class VTNodeLiteral (
+	text: String
+) extends VTNode {
+	
+	override def render (vars: Map[String, String]): String =
+		text
+	
+	override def toString: String =
+		val prefix           = "literal|"
+		val prefix_following = "       |"
+		val pt = text.split('\n')
+		(pt.headOption.map(prefix + _).getOrElse("") ::
+			pt.drop(1).map(prefix_following + _).toList)
+			.mkString("\n")
+	
+	override def serialize: String =
+		text
+			.replaceAll("/\\{", "//\\{")
+			.replaceAll("\\{", "/\\{")
+	
+}

src/main/scala/cc/sukazyo/cono/morny/util/var_text/VTNodeVar.scala

@@ -0,0 +1,16 @@
+package cc.sukazyo.cono.morny.util.var_text
+
+class VTNodeVar (
+	var_id: String
+) extends VTNode {
+	
+	override def render (vars: Map[String, String]): String =
+		vars.getOrElse(var_id, s"$${$var_id}")
+	
+	override def toString: String =
+		s"var_def(id={$var_id})"
+	
+	override def serialize: String =
+		s"{$var_id}"
+	
+}

src/main/scala/cc/sukazyo/cono/morny/util/var_text/Var.scala

@@ -0,0 +1,94 @@
+package cc.sukazyo.cono.morny.util.var_text
+
+import scala.language.implicitConversions
+
+/** A Var is a key-value pair, where the key is a string, and the value is also a string.
+  *
+  * This class is used to represent a variable in the [[VarText]].
+  *
+  * You can just call the [[Var]] constructor to create a new Var, or use the implicit
+  * conversion to create a var from a tuple of ([[String]], [[String]]), or use the extension
+  * method [[Var.StringAsVarText.asVar]] to convert a [[String]] to a var.
+  * 
+  * @since 2.0.0
+  *
+  * @param id The key of the variable, also known as var-id.
+  *
+  *           The var-id have some limitation on the characters that can be used in it.
+  *           For details, see [[Var.isLegalId]]. An illegal id will cause the constructor
+  *           throws [[IllegalArgumentException]].
+  *
+  * @param text The text content of the variable.
+  */
+case class Var (
+	id: String,
+	text: String
+) {
+	
+	// todo: id limitation
+	id.foreach { c =>
+		if (!Var.isLegalId(c))
+			throw new IllegalArgumentException(s"Character $c (${c.toInt}) is not allowed in a var id")
+	}
+	
+	/** Create a new Var with the same text but different id.
+	  * @since 2.0.0
+	  */
+	def asId (id: String): Var =
+		Var(id, this.text)
+	
+	/** Create a new Var with the same id but different text.
+	  * @since 2.0.0
+	  */
+		Var(this.id, text)
+	
+	/** Unpack this Var into a ([[String]], [[String]]) tuple.
+	  * @since 2.0.0
+	  */
+	def unpackKV: (String, String) =
+		(id, text)
+	
+}
+
+object Var {
+	
+	private val ID_AVAILABLE_SYMBOLS: Set[Char] =
+		"_-.*/\\|:#@%&?;,~"
+			.toCharArray.toSet
+	
+	/** Is this character is a legal var-id character.
+	  *
+	  * In other words, if this character is a letter, a digit, or one of the following
+	  * symbols (`_` `-` `.` `*` `/` `\` `|` `:` `#` `@` `%` `&` `?` `;` `,` `~`), this
+	  * character is allowed to shows in the [[Var.id]], we said this character is a
+	  * legal var-id character.
+	  *
+	  * @since 2.0.0
+	  * 
+	  * @return `true` if this character is legal, false otherwise.
+	  */
+	def isLegalId (c: Char): Boolean =
+		c.isLetterOrDigit || ID_AVAILABLE_SYMBOLS.contains(c)
+	
+	/** Convert a tuple of ([[String]], [[String]]) to a Var.
+	  * 
+	  * The first string of the tuple will be the [[Var.id]], and the second string
+	  * will be the [[Var.text]]
+	  * 
+	  * @since 2.0.0
+	  */
+	implicit def StrStrTupleAsVar (tuple: (String, Any)): Var =
+		Var(tuple._1, tuple._2.toString)
+	
+	/** @see [[asVar]] */
+	implicit class StringAsVarText (text: String):
+		/** Convert this string text to a [[Var]].
+		  * @since 2.0.0
+		  * @param id the var-id.
+		  * @return a [[Var]] that the [[Var.text text]] is this string, and the [[Var.id id]]
+		  *         is the given id.
+		  */
+		def asVar (id: String): Var =
+			Var(id, text)
+	
+}

src/main/scala/cc/sukazyo/cono/morny/util/var_text/VarText.scala

@@ -0,0 +1,151 @@
+package cc.sukazyo.cono.morny.util.var_text
+
+import cc.sukazyo.cono.morny.util.var_text.Var.isLegalId
+
+/** A text/string template that may contains some named replaceable variables. It's concept may
+  * be similar with scala's `StringContext` or `GString` in groovy.
+  *
+  * A [[VarText]] can contains a stream of [[VTNode]]s, each nodes can be a [[VTNodeLiteral]] or
+  * a [[VTNodeVar]].
+  *
+  * This can be rendered to a native [[String]] by calling [[render]] method with a set of [[Var]]
+  * variables. The [[VTNodeVar]] will look for the given [[Var]]s to find if there's a match, and
+  * replace itself with the value of the [[Var]], or output a placeholder if there's no match.
+  * 
+  * @since 2.0.0
+  */
+trait VarText {
+	
+	val nodes: List[VTNode]
+	
+	/** Render this VarText with the given `(var-key -> value)` map.
+	  * @since 2.0.0 
+	  */
+	def render (vars: Map[String, String]): String =
+		nodes.map(_.render(vars)).mkString
+	
+	/** Render this VarText with the given [[Var]]s seq.
+	  * @since 2.0.0 
+	  */
+	def render (vars: Var*): String =
+		render(Map.from(vars.toList.map(_.unpackKV)))
+	
+	/** Inspect the nodes of this VarText.
+	  * 
+	  * Each node will be rendered to a line with the node types prefix.
+	  * 
+	  * @since 2.0.0
+	  */
+	override def toString: String =
+		nodes.map(_.toString).mkString("\n")
+	
+	/** Serialize this VarText to a template string.
+	  * 
+	  * The return template string will be like the original template string that can be parsed
+	  * by the [[VarText.apply(String)]] parser.
+	  * 
+	  * @since 2.0.0 
+	  */
+	def serialize: String =
+		nodes.map(_.serialize).mkString
+	
+}
+
+object VarText {
+	
+	def apply (_nodes: VTNode*): VarText = new VarText:
+		override val nodes: List[VTNode] = _nodes.toList
+	
+	private val symbol_escape = '/'
+	private val symbol_var_start = '{'
+	private val symbol_var_end = '}'
+	
+	/** Parse a serialized VarText template string to a [[VarText]] object.
+	  * 
+	  * In the current standard, the `{<param>}` will be parsed to a [[VTNodeVar]], unless it
+	  * is escaped by the escape char `/`; And the escape char can and can only escape [[VTNodeVar]]
+	  * starter `{` or escape char `/` itself, any other chars following the escape char will
+	  * be treated both escape char itself and the following char as a normal char; And all others
+	  * will be parsed to [[VTNodeLiteral]].
+	  * 
+	  * @since 2.0.0
+	  */
+	def apply (template: String): VarText = {
+		
+		val _nodes = collection.mutable.ListBuffer[VTNode]()
+		
+		def newBuffer = StringBuilder()
+		var buffer: StringBuilder = newBuffer
+		def pushc (c: Char): Unit =
+			buffer += c
+		def buffer2literal(): Unit =
+			_nodes += VTNodeLiteral(buffer.toString)
+			buffer = newBuffer
+		def buffer2var(): Unit =
+			_nodes += VTNodeVar(buffer.toString drop 1)
+			buffer = newBuffer
+		sealed trait State
+		case class in_escape(it: Char) extends State
+		case object literal extends State
+		case object in_var_def extends State
+		var state: State = literal
+		
+		template.foreach { i =>
+			
+			def push(): Unit =
+				buffer += i
+			
+			state match
+				case in_escape(e) =>
+					i match
+						case f if f == symbol_var_start =>
+							state = literal
+							push()
+						case f if f == symbol_escape =>
+							state = literal
+							push()
+						case _ =>
+							state = literal
+							pushc(e)
+							push()
+				case _: in_var_def.type =>
+					i match
+						case f if f == symbol_var_end =>
+							buffer2var()
+							state = literal
+						case _ if isLegalId(i) =>
+							push()
+						case _ =>
+							state = literal
+							push()
+				case _: literal.type =>
+					i match
+						case f if f == symbol_escape =>
+							state = in_escape(i)
+						case f if f == symbol_var_start =>
+							buffer2literal()
+							state = in_var_def
+							push()
+						case _ =>
+							push()
+			
+		}
+		
+		state match
+			case in_escape(e) =>
+				pushc(e)
+			case _ =>
+		buffer2literal()
+		
+		new VarText:
+			override val nodes: List[VTNode] =
+				_nodes.toList
+					.filterNot {
+						case VTNodeLiteral(text) if text.isEmpty =>
+							true
+						case _ => false
+					}
+		
+	}
+	
+}

src/test/scala/cc/sukazyo/cono/morny/test/utils/var_text/VarTextTest.scala

@@ -0,0 +1,21 @@
+package cc.sukazyo.cono.morny.test.utils.var_text
+
+import cc.sukazyo.cono.morny.test.MornyTests
+import cc.sukazyo.cono.morny.util.var_text.{VarText, VTNodeLiteral, VTNodeVar}
+
+class VarTextTest extends MornyTests {
+	
+	"VarText template convertor works." in {
+		VarText("abcdefg {one_var}{following}it /{escaped}it and this is //double-escape-literal, with a /no-need-to-escape then {{non formatted}}xxx {missing_part")
+			.toString
+			.shouldEqual(VarText(
+				VTNodeLiteral("abcdefg "),
+				VTNodeVar("one_var"),
+				VTNodeVar("following"),
+				VTNodeLiteral("it {escaped}it and this is /double-escape-literal, with a /no-need-to-escape then "),
+				VTNodeLiteral("{{non formatted}}xxx "),
+				VTNodeLiteral("{missing_part"),
+			).toString)
+	}
+	
+}