Move expression explanation code to src/e.bqn

2 files changed, 54 insertions, 53 deletions

diff --git a/src/e.bqn b/src/e.bqn
new file mode 100644
index 00000000..5e8b4864
--- /dev/null
+++ b/src/e.bqn
@@ -0,0 +1,53 @@
+wh ← 10.75‿24
+pad← wh×2‿1
+to ← 1+wh÷2‿3
+t  ← 10
+
+ps ← At "class=Paren|stroke=currentColor|fill=none|stroke-width=1"
+rc ← At "class=code|stroke-width=1|rx=10"
+gr ← "g" At "font-family=BQN,monospace|font-size=18px"
+gt ← "g" At "text-anchor=middle"
+gb ← "g" At "class=codeCover|stroke-width=6|stroke-linejoin=round"
+gf ← "g" At "font-size=15px|opacity=0.9"
+Shadow ← {
+  t ← (⟨0,0‿¯2⟩+⌜𝕨) ("text" Attr Pos)⊸Enc¨ (⊢≍Highlight¨) ⥊¨𝕩
+  gt Enc ⟨gb,gf⟩ Enc¨<˘ t
+}
+
+Explain ← {
+  b‿const‿blk‿i ← 𝕨
+  ba‿bc‿bo‿bp ← '0'-˜⟨ # For each instruction, number of:
+    "11111000000000010000022000"  # Arguments
+    "000//232323223102303200121"  # Stack values consumed
+    "11111111111111011101111111"  # Stack values output
+    "00000110111001001101000100"  # Position determiner
+  ⟩
+  m ← { # Mask of instruction starts
+    a ← ba(⊣⊏˜≠⊸>×⊢)b
+    na← ∾⟜≠ (≠-(1+↕∘≠)⊸(»·⌈`×)⌾⌽) <⟜128 b
+    n ← 1+{(𝕩=⌜a) +˝∘× >⊏⟜na⍟𝕩↕≠a}↕3
+    ! ∧´ ↕∘≠⊸< n
+    Se←{(⊏˜𝕨)Se 1¨⌾((𝕩/𝕨)⊸⊏)𝕩}⍟(0=¯1⊑⊢)
+    (≠↑∾⟜≠Se 1∾0¨) n
+  }
+  mb‿mi ← m⊸/¨ b‿i
+  mi↓˜↩¯1
+
+  r←+`(mb⊏bo)-na←mb⊏bc
+  ! 1=¯1⊑r
+  p←((¯1↓r)⍋⊸⊏○⍋(⊏⟜r+⊒))⊸⊏/na
+  j←¯1↓mi⊏˜⊏˜⍟≠{s←𝕩⊏˜g←⍋𝕩⋄(g/˜(⊒s)=s⊏mb⊏bp)⌾((⍷s)⊸⊏)↕≠mb}p
+  je←j∾¯1.25
+  d←+`⊸×f←0<na
+  f↑˜↩≠p
+  q←(/f∨j≠p⊏je) (⊏≍⊣) p
+
+  pd ← <⊸∾⟜⌽˘˜˝ q ⊏ ⍉wh×0.6‿0.1+je≍d
+  dim← (wh×⟨≠𝕩,2+⌈´d⟩)+2‿0×pad
+  (512‿0⊸⌈⊸(⊣∾˜(t+pad)-˜-˜÷2˙)dim+2×t) SVG gr Enc ∾⥊¨⟨
+    <"rect" Elt rc∾(Pos-pad)∾"width"‿"height"≍˘FmtNum¨dim
+    <"text" Enc Highlight 𝕩
+    (<"path" Elt ps∾"d"≍○<·∾"MVH"∾⟜Fmt¨⊢)˘ pd
+    mi ((to+wh×≍)¨Shadow⊏⟜𝕩)⟜(⊏⟜d)○((¬f)⊸/) p
+  ⟩
+}
diff --git a/tutorial/evalexp.bqn b/tutorial/evalexp.bqn
index eff3aad2..048181ee 100644
--- a/tutorial/evalexp.bqn
+++ b/tutorial/evalexp.bqn
@@ -1,54 +1,2 @@
-wh ← 10.75‿24
-pad← wh×2‿1
-to ← 1+wh÷2‿3
-t  ← 10
-
-ps ← At "class=Paren|stroke=currentColor|fill=none|stroke-width=1"
-rc ← At "class=code|stroke-width=1|rx=10"
-gr ← "g" At "font-family=BQN,monospace|font-size=18px"
-gt ← "g" At "text-anchor=middle"
-gb ← "g" At "class=codeCover|stroke-width=6|stroke-linejoin=round"
-gf ← "g" At "font-size=15px|opacity=0.9"
-Shadow ← {
-  t ← (⟨0,0‿¯2⟩+⌜𝕨) ("text" Attr Pos)⊸Enc¨ (⊢≍Highlight¨) ⥊¨𝕩
-  gt Enc ⟨gb,gf⟩ Enc¨<˘ t
-}
-
 Compile ← (↕62)⊸(•Import "../src/c.bqn")
-DrawEval←{
-  b‿const‿blk‿i ← Compile 𝕩
-  ba‿bc‿bo‿bp ← '0'-˜⟨ # For each instruction, number of:
-    "11111000000000010000022000"  # Arguments
-    "000//232323223102303200121"  # Stack values consumed
-    "11111111111111011101111111"  # Stack values output
-    "00000110111001001101000100"  # Position determiner
-  ⟩
-  m ← { # Mask of instruction starts
-    a ← ba(⊣⊏˜≠⊸>×⊢)b
-    na← ∾⟜≠ (≠-(1+↕∘≠)⊸(»·⌈`×)⌾⌽) <⟜128 b
-    n ← 1+{(𝕩=⌜a) +˝∘× >⊏⟜na⍟𝕩↕≠a}↕3
-    ! ∧´ ↕∘≠⊸< n
-    Se←{(⊏˜𝕨)Se 1¨⌾((𝕩/𝕨)⊸⊏)𝕩}⍟(0=¯1⊑⊢)
-    (≠↑∾⟜≠Se 1∾0¨) n
-  }
-  mb‿mi ← m⊸/¨ b‿i
-  mi↓˜↩¯1
-
-  r←+`(mb⊏bo)-na←mb⊏bc
-  ! 1=¯1⊑r
-  p←((¯1↓r)⍋⊸⊏○⍋(⊏⟜r+⊒))⊸⊏/na
-  j←¯1↓mi⊏˜⊏˜⍟≠{s←𝕩⊏˜g←⍋𝕩⋄(g/˜(⊒s)=s⊏mb⊏bp)⌾((⍷s)⊸⊏)↕≠mb}p
-  je←j∾¯1.25
-  d←+`⊸×f←0<na
-  f↑˜↩≠p
-  q←(/f∨j≠p⊏je) (⊏≍⊣) p
-
-  pd ← <⊸∾⟜⌽˘˜˝ q ⊏ ⍉wh×0.6‿0.1+je≍d
-  dim← (wh×⟨≠𝕩,2+⌈´d⟩)+2‿0×pad
-  (512‿0⊸⌈⊸(⊣∾˜(t+pad)-˜-˜÷2˙)dim+2×t) SVG gr Enc ∾⥊¨⟨
-    <"rect" Elt rc∾(Pos-pad)∾"width"‿"height"≍˘FmtNum¨dim
-    <"text" Enc Highlight 𝕩
-    (<"path" Elt ps∾"d"≍○<·∾"MVH"∾⟜Fmt¨⊢)˘ pd
-    mi ((to+wh×≍)¨Shadow⊏⟜𝕩)⟜(⊏⟜d)○((¬f)⊸/) p
-  ⟩
-}
+DrawEval ← Compile⊸(⍎ ∾∾⟜(@+10)¨ •LNS "../src/e.bqn")