Config

guinep/src/main/scala/model.scala

@@ -5,17 +5,7 @@ import scala.quoted.*
 private[guinep] object model {
   case class Fun(name: String, form: Form, run: List[Any] => String)
 
-  case class Form(inputs: Seq[FormElement], namedFormElements: Map[String, FormElement]) {
-    def formElementsJSONRepr =
-      val elems = this.inputs.map(_.toJSONRepr).mkString(",")
-      s"[$elems]"
-    def namedFormElementsJSONRepr: String =
-      val entries = this.namedFormElements.toList.map { (name, formElement) =>
-        s""""$name": ${formElement.toJSONRepr}"""
-      }
-      .mkString(",")
-      s"{$entries}"
-  }
+  case class Form(inputs: Seq[FormElement], namedFormElements: Map[String, FormElement])
   object Form:
     given ToExpr[Form] with
       def apply(form: Form)(using Quotes): Expr[Form] = form match
@@ -100,35 +90,6 @@ private[guinep] object model {
       case FieldSet(_, _) => 8
       case NamedRef(_, _) => 9
 
-    def toJSONRepr: String = this match
-      case FormElement.FieldSet(name, elements) =>
-        s"""{ "name": '$name', "type": 'fieldset', "elements": [${elements.map(_.toJSONRepr).mkString(",")}] }"""
-      case FormElement.TextInput(name) =>
-        s"""{ "name": '$name', "type": 'text' }"""
-      case FormElement.CharInput(name) =>
-        s"""{ "name": '$name', "type": 'char' }"""
-      case FormElement.NumberInput(name, _) =>
-        s"""{ "name": '$name', "type": 'number' }"""
-      case FormElement.FloatingNumberInput(name, _) =>
-        s"""{ "name": '$name', "type": 'float' }"""
-      case FormElement.CheckboxInput(name) =>
-        s"""{ "name": '$name', "type": 'checkbox' }"""
-      case FormElement.Dropdown(name, options) =>
-        // TODO(kπ) this sortBy isn't 100% sure to be working (the only requirement is for the first constructor to not be recursive; this is a graph problem, sorta)
-        s"""{ "name": '$name', "type": 'dropdown', "options": [${options.sortBy(_._2).map { case (k, v) => s"""{"name": "$k", "value": ${v.toJSONRepr}}""" }.mkString(",")}] }"""
-      case FormElement.ListInput(name, element, _) =>
-        s"""{ "name": '$name', "type": 'list', "element": ${element.toJSONRepr} }"""
-      case FormElement.TextArea(name, rows, cols) =>
-        s"""{ "name": '$name', "type": 'textarea', "rows": ${rows.getOrElse("")}, "cols": ${cols.getOrElse("")} }"""
-      case FormElement.DateInput(name) =>
-        s"""{ "name": '$name', "type": 'date' }"""
-      case FormElement.EmailInput(name) =>
-        s"""{ "name": '$name', "type": 'email' }"""
-      case FormElement.PasswordInput(name) =>
-        s"""{ "name": '$name', "type": 'password' }"""
-      case FormElement.NamedRef(name, ref) =>
-        s"""{ "name": '$name', "ref": '$ref', "type": 'namedref' }"""
-
   object FormElement:
     given ToExpr[FormElement] with
       def apply(formElement: FormElement)(using Quotes): Expr[FormElement] = formElement match

web/src/main/scala/api.scala

@@ -1,6 +1,43 @@
 package guinep
 
 /**
+  * Creates and instance of GUInep web interface with the given configuration.
+  * 
+  * To start the web server, call the `apply` method with the functions to be exposed.
+  * 
+  * To change the configuration, call the `withSetConfig` or `withModifyConfig` methods.
+  * 
+  * @param config the configuration for the web interface
+  * @example {{{
+  *  def add(a: Int, b: Int) = a + b
+  *  def greet(name: String) = s"Hello, $name!"
+  *  @main def run = guinep.web(add, greet)
+  * }}}
+  */
+def web: GuinepWeb =
+  GuinepWeb()
+
+/**
+  * Configuration for the GUInep web interface.
+  *
+  * @param requireNonNullableInputs when set, all non-nullable types will correspond to required inputs in the frontend
+  */
+case class GuinepWebConfig(
+  requireNonNullableInputs: Boolean = false
+)
+
+object GuinepWebConfig:
+  def default: GuinepWebConfig =
+    GuinepWebConfig()
+
+private case class GuinepWeb(config: GuinepWebConfig = GuinepWebConfig.default) {
+  def withSetConfig(config: GuinepWebConfig): Unit =
+    this.copy(config = config)
+
+  def withModifyConfig(f: GuinepWebConfig => GuinepWebConfig): Unit =
+    withSetConfig(f(config))
+
+  /**
   * Starts a web server with the endpoints for running the given functions and
   * an automatically derived frontend for calling them.
   *
@@ -11,13 +48,17 @@ package guinep
   *  @main def run = guinep.web(add, greet)
   * }}}
   */
-inline def web(inline functions: Any*): Unit =
-  val functionsInfos = macros.funInfos(functions)
-  val functionsInfosMap = functionsInfos.groupBy(_.name)
-  if functionsInfosMap.exists(_._2.size > 1) then
-    println(
-      s"""|Duplicate function names found: ${functionsInfosMap.filter(_._2.size > 1).keys.mkString(", ")}
-          |Ignoring duplicates""".stripMargin
+  inline def apply(inline functions: Any*): Unit =
+    val functionsInfos = macros.funInfos(functions)
+    val functionsInfosMap = functionsInfos.groupBy(_.name)
+    if functionsInfosMap.exists(_._2.size > 1) then
+      println(
+        s"""|Duplicate function names found: ${functionsInfosMap.filter(_._2.size > 1).keys.mkString(", ")}
+            |Ignoring duplicates""".stripMargin
+      )
+    println("Starting GUInep web server at http://localhost:8090/")
+    webgen.genWeb(
+      funs = functionsInfos.distinct.map(fun => fun.name -> fun),
+      config = config
     )
-  println("Starting GUInep web server at http://localhost:8090/")
-  webgen.genWeb(functionsInfos.distinct.map(fun => fun.name -> fun))
+}

web/src/main/scala/htmlgen.scala

@@ -2,13 +2,15 @@ package guinep
 
 import guinep.*
 import guinep.model.*
+import guinep.serialization.*
 import zio.*
 import zio.http.*
 import zio.http.template.*
 import zio.http.codec.*
 
 private[guinep] trait HtmlGen {
   val funs: Seq[(String, Fun)]
+  val config: GuinepWebConfig
   def generateHtml =
     html(
       head(

web/src/main/scala/serialization.scala

@@ -78,3 +78,44 @@ private[guinep] object serialization:
           case guinep.model.Types.ListType.Seq => res.toSeq
           case guinep.model.Types.ListType.Vector => res.toVector
       case _ => Left(s"Unsupported form element: $formElement")
+
+  extension (form: Form)
+    def formElementsJSONRepr =
+      val elems = form.inputs.map(_.toJSONRepr).mkString(",")
+      s"[$elems]"
+    def namedFormElementsJSONRepr: String =
+      val entries = form.namedFormElements.toList.map { (name, formElement) =>
+        s""""$name": ${formElement.toJSONRepr}"""
+      }
+      .mkString(",")
+      s"{$entries}"
+
+  extension (formElement: FormElement)
+    def toJSONRepr: String = formElement match
+      case FormElement.FieldSet(name, elements) =>
+        s"""{ "name": '$name', "type": 'fieldset', "elements": [${elements.map(_.toJSONRepr).mkString(",")}] }"""
+      case FormElement.TextInput(name) =>
+        s"""{ "name": '$name', "type": 'text' }"""
+      case FormElement.CharInput(name) =>
+        s"""{ "name": '$name', "type": 'char' }"""
+      case FormElement.NumberInput(name, _) =>
+        s"""{ "name": '$name', "type": 'number' }"""
+      case FormElement.FloatingNumberInput(name, _) =>
+        s"""{ "name": '$name', "type": 'float' }"""
+      case FormElement.CheckboxInput(name) =>
+        s"""{ "name": '$name', "type": 'checkbox' }"""
+      case FormElement.Dropdown(name, options) =>
+        // TODO(kπ) this sortBy isn't 100% sure to be working (the only requirement is for the first constructor to not be recursive; this is a graph problem, sorta)
+        s"""{ "name": '$name', "type": 'dropdown', "options": [${options.sortBy(_._2).map { case (k, v) => s"""{"name": "$k", "value": ${v.toJSONRepr}}""" }.mkString(",")}] }"""
+      case FormElement.ListInput(name, element, _) =>
+        s"""{ "name": '$name', "type": 'list', "element": ${element.toJSONRepr} }"""
+      case FormElement.TextArea(name, rows, cols) =>
+        s"""{ "name": '$name', "type": 'textarea', "rows": ${rows.getOrElse("")}, "cols": ${cols.getOrElse("")} }"""
+      case FormElement.DateInput(name) =>
+        s"""{ "name": '$name', "type": 'date' }"""
+      case FormElement.EmailInput(name) =>
+        s"""{ "name": '$name', "type": 'email' }"""
+      case FormElement.PasswordInput(name) =>
+        s"""{ "name": '$name', "type": 'password' }"""
+      case FormElement.NamedRef(name, ref) =>
+        s"""{ "name": '$name', "ref": '$ref', "type": 'namedref' }"""

web/src/main/scala/webgen.scala

@@ -13,8 +13,11 @@ import scala.util.chaining.*
 
 private[guinep] object webgen {
 
-  def genWeb(funs: Seq[(String, Fun)]): Unit = {
-    val ws = WebServer(funs)
+  def genWeb(
+    funs: Seq[(String, Fun)],
+    config: GuinepWebConfig
+  ): Unit = {
+    val ws = WebServer(funs, config)
     val runtime = Runtime.default
     Unsafe.unsafe { implicit unsafe =>
       runtime.unsafe.run(
@@ -24,8 +27,12 @@ private[guinep] object webgen {
     }
   }
 
-  class WebServer(val funs: Seq[(String, Fun)]) extends HtmlGen {
+  class WebServer(
+    val funs: Seq[(String, Fun)],
+    val config: GuinepWebConfig
+  ) extends HtmlGen {
     val funsMap = funs.toMap
+
     val app: HttpApp[Any] = Routes(
       Method.GET / PathCodec.empty ->
         handler(Response.html(generateHtml)),