Merge pull request #76 from andreasKroepelin/fancy-alternatives

Implement more versions of alternatives

logic.typ

@@ -127,33 +127,71 @@
   }
 }
 
-#let alternatives(
-  start: 1,
-  position: bottom + left,
-  repeat-last: false,
-  ..children
-) = {
+#let alternatives-match(subslides-contents, position: bottom + left) = {
+  let subslides-contents = if type(subslides-contents) == "dictionary" {
+    subslides-contents.pairs()
+  } else {
+    subslides-contents
+  }
+
+  let subslides = subslides-contents.map(it => it.first())
+  let contents = subslides-contents.map(it => it.last())
   style(styles => {
-    let sizes = children.pos().map(c => measure(c, styles))
+    let sizes = contents.map(c => measure(c, styles))
     let max-width = calc.max(..sizes.map(sz => sz.width))
     let max-height = calc.max(..sizes.map(sz => sz.height))
-    for (idx, child) in children.pos().enumerate() {
-      let last = idx == children.pos().len() - 1
-      let visible-subslides = if last and repeat-last {
-        (beginning: start + idx)
-      } else {
-        start + idx
-      }
-
-      only(visible-subslides, box(
+    for (subslides, content) in subslides-contents {
+      only(subslides, box(
         width: max-width,
         height: max-height,
-        align(position, child)
+        align(position, content)
       ))
     }
   })
 }
 
+#let alternatives(
+  start: 1,
+  repeat-last: false,
+  ..args
+) = {
+  let contents = args.pos()
+  let kwargs = args.named()
+  let subslides = range(start, start + contents.len())
+  if repeat-last {
+    subslides.last() = (beginning: subslides.last())
+  }
+  alternatives-match(subslides.zip(contents), ..kwargs)
+}
+
+#let alternatives-fn(
+  start: 1,
+  end: none,
+  count: none,
+  ..kwargs,
+  fn
+) = {
+  let end = if end == none {
+    if count == none {
+      panic("You must specify either end or count.")
+    } else {
+      start + count
+    }
+  } else {
+    end
+  }
+
+  let subslides = range(start, end)
+  let contents = subslides.map(fn)
+  alternatives-match(subslides.zip(contents), ..kwargs.named())
+}
+
+#let alternatives-cases(cases, fn, ..kwargs) = {
+  let idcs = range(cases.len())
+  let contents = idcs.map(fn)
+  alternatives-match(cases.zip(contents), ..kwargs.named())
+}
+
 #let line-by-line(start: 1, mode: "invisible", body) = {
   let items = if repr(body.func()) == "sequence" {
     body.children

polylux.typ

@@ -1,5 +1,5 @@
 #import "themes/themes.typ"
 #import "logic.typ"
-#import "logic.typ": polylux-slide, uncover, only, alternatives, one-by-one, line-by-line, pause, enable-handout-mode
+#import "logic.typ": polylux-slide, uncover, only, alternatives, alternatives-match, alternatives-fn, alternatives-cases, one-by-one, line-by-line, pause, enable-handout-mode
 #import "helpers.typ"
 #import "helpers.typ": polylux-outline, fit-to-height, pdfpc

tests/alternatives.typ

@@ -11,3 +11,31 @@
 
   #uncover(5)[You can go now.]
 ]
+
+#polylux-slide[
+  == Test that `alternatives-match` works
+
+  #alternatives-match(position: center, (
+    "-2": [beginning],
+    "3, 5": [main part],
+    "4": [short break],
+    "6-" : [end]
+  ))
+
+  #uncover("1-8")[I am always here, for technical reasons.]
+]
+
+#polylux-slide[
+  == Test that `alternatives-cases` works
+
+  #alternatives-cases(("1,3,4", "2,5", "6"), case => {
+    set text(fill: lime) if case == 1
+    lorem(10)
+  })
+]
+
+#polylux-slide[
+  == Test that `alternatives-fn` works
+
+  #alternatives-fn(count: 5, subslide => numbering("(i)", subslide))
+]