Implement solution.

examples/exam-006.typ

@@ -0,0 +1,69 @@
+#import "../g-exam.typ": g-exam, g-question, g-subquestion, g-solution
+
+#show: g-exam.with(
+  author: (
+    name: "Andrés Jorge Giménez Muñoz", 
+    email: "[email protected]", 
+    watermark: "Teacher: andres",
+  ),
+  school: (
+    name: "Sunrise Secondary School",
+    logo: read("./logo.png", encoding: none),
+  ),
+  exam-info: (
+    academic-period: "Academic year 2023/2024",
+    academic-level: "1º Secondary Education",
+    academic-subject: "Mathematics",
+    number: "2nd Assessment 1st Exam",
+    content: "Radicals and fractions",
+    model: "Model A"
+  ),
+
+  languaje: "en",
+  decimal-separator: ",",
+  date: "November 21, 2023",
+  show-studen-data: "first-page",
+  show-grade-table: false,
+  question-point-position: right,
+  show-solution: true,
+  clarifications: "Answer the questions in the spaces provided. If you run out of room for an answer, continue on the back of the page."
+)
+
+#g-question[Given the equation $x^n + y^n = z^n$ for $(x,y,z)$ and $n$ positive integers.] 
+#g-subquestion(point: 10)[For what values of $n$ is the statement in the previous question true?]
+
+#g-solution[
+  I know the demostration, but there's no room on the margin. For any clarification ask Andrew Whilst.
+  #v(1fr)
+]
+
+#g-subquestion(point: 10)[For $n=2$ there's a theorem with a special name. What's that name?
+
+  #g-solution[
+    Pythagorean theorem.
+  ]
+#v(1fr)
+] 
+
+
+#g-subquestion(point: 10)[What famous mathematician had an elegant proof for this theorem but
+there was not enough space in the margin to write it down?].
+#v(1fr)
+
+#g-question(point: 20)[Prove that the real part of all non-trivial zeros of the function $zeta(z) "is" 1/2$].
+
+#g-solution(show-solution: true, 
+  alternative-content: [#v(1fr)]
+  )[
+    I'm working on it. When I have the solution, I'll let you know.... \
+
+    #v(5pt)
+  ]
+
+#g-solution(show-solution: false, 
+  alternative-content: [#v(1fr)]
+  )[
+    I'm working on it. When I have the solution, I'll let you know.... \
+
+    #v(5pt)
+  ]

g-exam.typ

@@ -4,8 +4,8 @@
 #let __g-question-point = state("g-question-point", 0)
 #let __g-question-point-position-state = state("g-question-point-position", left)
 
-
 #let __g-localization = state("localization")
+#let __g-show-solution = state("g-show-solution", false)
 
 #let __g-default-localization = (
     grade-table-queston: "Question",
@@ -229,6 +229,29 @@
   )
 }
 
+#let g-solution(
+    alternative-content: none,
+    show-solution: none,
+    body) = {
+      assert(alternative-content == none or type(alternative-content) == "content",
+        message: "Invalid alternative-content value")
+
+      assert(show-solution in (none, true, false),
+        message: "Invalid show-solution solution value")
+
+      locate(loc => {
+        let show-solution = if show-solution == none { __g-show-solution.final(loc) } else { show-solution }
+
+        if show-solution == true {
+          body
+        }
+        else {
+          alternative-content
+        }
+      }
+    )
+}
+
 #let __g-show_clarifications = (clarifications: none) => {
   if clarifications != none {
     let clarifications-content = []
@@ -302,6 +325,7 @@
   show-grade-table: true,
   decimal-separator: ".",
   question-point-position: left,
+  show-solution: false,
   body,
 ) = {
 
@@ -314,6 +338,9 @@
   assert(decimal-separator in (".", ","),
       message: "Invalid decimal separator")
 
+  assert(show-solution in (true, false),
+      message: "Invalid show solution value")
+
   let __show-watermark = (
       author: (
           name: "",
@@ -585,6 +612,8 @@
     )
     v(10pt)
   }
+
+  __g-show-solution.update(show-solution)
 
   // show heading.where(level: 1): it => {
   //   set block(above: 1.2em, below: 1em)