From 668040f6c61f55b061665185c97eaa19c0d96555 Mon Sep 17 00:00:00 2001
From: Simon Forman <sforman@hushmail.com>
Date: Mon, 19 Sep 2022 13:22:31 -0700
Subject: [PATCH] Add a flowchart for the interpreter.

Using PlantUML.
---
 README.md                               |  3 +++
 docs/_joy_interpreter_flowchart_url.txt |  1 +
 docs/html/index.html                    |  1 +
 docs/html/joy_interpreter_flowchart.svg | 32 +++++++++++++++++++++++++
 joy_interpreter_flowchart.svg           | 32 +++++++++++++++++++++++++
 5 files changed, 69 insertions(+)
 create mode 100644 docs/_joy_interpreter_flowchart_url.txt
 create mode 100644 docs/html/joy_interpreter_flowchart.svg
 create mode 100644 joy_interpreter_flowchart.svg

diff --git a/README.md b/README.md
index f6149a8..00b6a9e 100644
--- a/README.md
+++ b/README.md
@@ -135,6 +135,9 @@ available functions of the Joy system.  Together the stack, expression, and dict
 are the entire state of the Joy interpreter.
 
 
+![joy_interpreter_flowchart.svg](/joy_interpreter_flowchart.svg)
+
+
 ### Stack / Quote / List / Sequence
 
 When talking about Joy we use the terms "stack", "quote", "sequence",
diff --git a/docs/_joy_interpreter_flowchart_url.txt b/docs/_joy_interpreter_flowchart_url.txt
new file mode 100644
index 0000000..ffa48ab
--- /dev/null
+++ b/docs/_joy_interpreter_flowchart_url.txt
@@ -0,0 +1 @@
+//www.plantuml.com/plantuml/png/NP0xRiCm38PtdO905sTe3Y0FpIMApafCruGbqg3e9hvz6Jj2WIuIXVy1yRjKIsfhoM4VGhXFb14wV2oAjP8mK3sVpoU_e6FXTooBRQS04B_HWF5XOAW5HfK2Vx7U7JH2zzHQXKt8qDMjN2K_6mx7yGPY6EXc7aswVJGpos44U5CSeYQg29yyizpvItJeN-fLCStxZDaTtOQr1MCMcTS5nfNt-XQ9-9FocWp_ASW3ZQ4LPV8DqkkxSLdhTAmhR0BEx3RteMNyRFWEI26oQ4dPkP3rZbYMS76Ny_u5
\ No newline at end of file
diff --git a/docs/html/index.html b/docs/html/index.html
index 3d9741e..59d5da3 100644
--- a/docs/html/index.html
+++ b/docs/html/index.html
@@ -112,6 +112,7 @@ Functions receive the current stack, expression, and dictionary and return the n
 <p>The <strong>dictionary</strong> associates symbols (strings) with Joy expressions that define the
 available functions of the Joy system.  Together the stack, expression, and dictionary
 are the entire state of the Joy interpreter.</p>
+<p><img alt="joy_interpreter_flowchart.svg" src="/joy_interpreter_flowchart.svg"></p>
 <h3>Stack / Quote / List / Sequence</h3>
 <p>When talking about Joy we use the terms "stack", "quote", "sequence",
 "list", and others to mean the same thing: a simple linear datatype that
diff --git a/docs/html/joy_interpreter_flowchart.svg b/docs/html/joy_interpreter_flowchart.svg
new file mode 100644
index 0000000..c7d9030
--- /dev/null
+++ b/docs/html/joy_interpreter_flowchart.svg
@@ -0,0 +1,32 @@
+<?xml version="1.0" encoding="UTF-8" standalone="no"?>
+<svg xmlns="http://www.w3.org/2000/svg" xmlns:xlink="http://www.w3.org/1999/xlink" contentStyleType="text/css" height="478px" preserveAspectRatio="none" style="width:558px;height:478px;background:#FFFFFF;" version="1.1" viewBox="0 0 558 478" width="558px" zoomAndPan="magnify"><defs/><g><ellipse cx="320.5" cy="20" fill="#222222" rx="10" ry="10" style="stroke:#222222;stroke-width:1.0;"/><rect fill="#F1F1F1" height="33.9688" rx="12.5" ry="12.5" style="stroke:#181818;stroke-width:0.5;" width="206" x="217.5" y="105.7104"/><text fill="#000000" font-family="sans-serif" font-size="12" lengthAdjust="spacing" textLength="186" x="227.5" y="126.8491">get next term from expression</text><polygon fill="#F1F1F1" points="296,159.6792,345,159.6792,357,171.6792,345,183.6792,296,183.6792,284,171.6792,296,159.6792" style="stroke:#181818;stroke-width:0.5;"/><text fill="#000000" font-family="sans-serif" font-size="11" lengthAdjust="spacing" textLength="49" x="296" y="175.4873">term is...</text><text fill="#000000" font-family="sans-serif" font-size="11" lengthAdjust="spacing" textLength="41" x="243" y="169.085">symbol</text><text fill="#000000" font-family="sans-serif" font-size="11" lengthAdjust="spacing" textLength="32" x="357" y="169.085">literal</text><polygon fill="#F1F1F1" points="137,193.6792,257,193.6792,269,205.6792,257,217.6792,137,217.6792,125,205.6792,137,193.6792" style="stroke:#181818;stroke-width:0.5;"/><text fill="#000000" font-family="sans-serif" font-size="11" lengthAdjust="spacing" textLength="120" x="137" y="209.4873">symbol in dictionary?</text><text fill="#000000" font-family="sans-serif" font-size="11" lengthAdjust="spacing" textLength="14" x="111" y="203.085">no</text><text fill="#000000" font-family="sans-serif" font-size="11" lengthAdjust="spacing" textLength="21" x="269" y="203.085">yes</text><rect fill="#FF0000" height="33.9688" rx="12.5" ry="12.5" style="stroke:#181818;stroke-width:0.5;" width="142" x="44" y="227.6792"/><text fill="#000000" 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style="stroke:#222222;stroke-width:1.0;"/><ellipse cx="320.5" cy="456.5854" fill="#222222" rx="6" ry="6" style="stroke:#111111;stroke-width:1.0;"/><line style="stroke:#181818;stroke-width:1.0;" x1="115" x2="115" y1="261.6479" y2="281.6479"/><line style="stroke:#181818;stroke-width:1.0;" x1="115" x2="24" y1="281.6479" y2="281.6479"/><polygon fill="#181818" points="34,277.6479,24,281.6479,34,285.6479,30,281.6479" style="stroke:#181818;stroke-width:1.0;"/><line style="stroke:#181818;stroke-width:1.0;" x1="279" x2="279" y1="261.6479" y2="281.6479"/><polygon fill="#181818" points="275,271.6479,279,281.6479,283,271.6479,279,275.6479" style="stroke:#181818;stroke-width:1.0;"/><line style="stroke:#181818;stroke-width:1.0;" x1="125" x2="115" y1="205.6792" y2="205.6792"/><line style="stroke:#181818;stroke-width:1.0;" x1="115" x2="115" y1="205.6792" y2="227.6792"/><polygon fill="#181818" points="111,217.6792,115,227.6792,119,217.6792,115,221.6792" style="stroke:#181818;stroke-width:1.0;"/><line 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points="316.5,95.7104,320.5,105.7104,324.5,95.7104,320.5,99.7104" style="stroke:#181818;stroke-width:1.0;"/><line style="stroke:#181818;stroke-width:1.0;" x1="320.5" x2="320.5" y1="349.6167" y2="359.6167"/><line style="stroke:#181818;stroke-width:1.0;" x1="320.5" x2="532" y1="359.6167" y2="359.6167"/><polygon fill="#181818" points="528,220.2612,532,210.2612,536,220.2612,532,216.2612" style="stroke:#181818;stroke-width:1.0;"/><line style="stroke:#181818;stroke-width:1.0;" x1="532" x2="532" y1="62" y2="359.6167"/><line style="stroke:#181818;stroke-width:1.0;" x1="532" x2="375" y1="62" y2="62"/><polygon fill="#181818" points="385,58,375,62,385,66,381,62" style="stroke:#181818;stroke-width:1.0;"/><line style="stroke:#181818;stroke-width:1.0;" x1="266" x2="24" y1="62" y2="62"/><polygon fill="#181818" points="20,206.2612,24,216.2612,28,206.2612,24,210.2612" style="stroke:#181818;stroke-width:1.0;"/><line style="stroke:#181818;stroke-width:1.0;" x1="24" x2="24" y1="62" y2="371.6167"/><line style="stroke:#181818;stroke-width:1.0;" x1="24" x2="320.5" y1="371.6167" y2="371.6167"/><line style="stroke:#181818;stroke-width:1.0;" x1="320.5" x2="320.5" y1="371.6167" y2="391.6167"/><polygon fill="#181818" points="316.5,381.6167,320.5,391.6167,324.5,381.6167,320.5,385.6167" style="stroke:#181818;stroke-width:1.0;"/><line style="stroke:#181818;stroke-width:1.0;" x1="320.5" x2="320.5" y1="30" y2="50"/><polygon fill="#181818" points="316.5,40,320.5,50,324.5,40,320.5,44" style="stroke:#181818;stroke-width:1.0;"/><line style="stroke:#181818;stroke-width:1.0;" x1="320.5" x2="320.5" y1="425.5854" y2="445.5854"/><polygon fill="#181818" points="316.5,435.5854,320.5,445.5854,324.5,435.5854,320.5,439.5854" style="stroke:#181818;stroke-width:1.0;"/><!--MD5=[ec377fca7e5f6ceacaa83c32e04a919c]
+@startuml
+start
+
+while (expression is...) is (non-empty)
+  :get next term from expression;
+  if (term is...) then (symbol)
+    if (symbol in dictionary?) then (no)
+      #red:raise UnknownWord;
+      break
+    else (yes)
+      :lookup function;
+      :evaluate function;
+    endif
+  else (literal)
+    :push term onto stack;
+  endif
+endwhile (empty)
+
+:normal exit;
+stop
+@enduml
+
+PlantUML version 1.2022.8beta8(Unknown compile time)
+(GPL source distribution)
+Java Runtime: Java(TM) SE Runtime Environment
+JVM: Java HotSpot(TM) 64-Bit Server VM
+Default Encoding: UTF-8
+Language: en
+Country: US
+--></g></svg>
\ No newline at end of file
diff --git a/joy_interpreter_flowchart.svg b/joy_interpreter_flowchart.svg
new file mode 100644
index 0000000..c7d9030
--- /dev/null
+++ b/joy_interpreter_flowchart.svg
@@ -0,0 +1,32 @@
+<?xml version="1.0" encoding="UTF-8" standalone="no"?>
+<svg xmlns="http://www.w3.org/2000/svg" xmlns:xlink="http://www.w3.org/1999/xlink" contentStyleType="text/css" height="478px" preserveAspectRatio="none" style="width:558px;height:478px;background:#FFFFFF;" version="1.1" viewBox="0 0 558 478" width="558px" zoomAndPan="magnify"><defs/><g><ellipse cx="320.5" cy="20" fill="#222222" rx="10" ry="10" style="stroke:#222222;stroke-width:1.0;"/><rect fill="#F1F1F1" height="33.9688" rx="12.5" ry="12.5" style="stroke:#181818;stroke-width:0.5;" width="206" x="217.5" y="105.7104"/><text fill="#000000" font-family="sans-serif" font-size="12" lengthAdjust="spacing" textLength="186" x="227.5" y="126.8491">get next term from expression</text><polygon fill="#F1F1F1" points="296,159.6792,345,159.6792,357,171.6792,345,183.6792,296,183.6792,284,171.6792,296,159.6792" style="stroke:#181818;stroke-width:0.5;"/><text fill="#000000" font-family="sans-serif" font-size="11" lengthAdjust="spacing" textLength="49" x="296" y="175.4873">term is...</text><text 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+@startuml
+start
+
+while (expression is...) is (non-empty)
+  :get next term from expression;
+  if (term is...) then (symbol)
+    if (symbol in dictionary?) then (no)
+      #red:raise UnknownWord;
+      break
+    else (yes)
+      :lookup function;
+      :evaluate function;
+    endif
+  else (literal)
+    :push term onto stack;
+  endif
+endwhile (empty)
+
+:normal exit;
+stop
+@enduml
+
+PlantUML version 1.2022.8beta8(Unknown compile time)
+(GPL source distribution)
+Java Runtime: Java(TM) SE Runtime Environment
+JVM: Java HotSpot(TM) 64-Bit Server VM
+Default Encoding: UTF-8
+Language: en
+Country: US
+--></g></svg>
\ No newline at end of file