From 3a5daad8af298ebd0612eb21595d44fb15650a21 Mon Sep 17 00:00:00 2001
From: Brad Nelson <flagxor@gmail.com>
Date: Sat, 10 May 2025 12:41:18 -0700
Subject: [PATCH] Adding jotblk sample.

A web editor that embeds uEforth.
---
 .gitignore                     |   1 +
 attic/jotblk/Makefile          |  12 +
 attic/jotblk/README.md         |  20 ++
 attic/jotblk/app.yaml          |  17 +
 attic/jotblk/dstore.sh         |   2 +
 attic/jotblk/main.py           |  81 +++++
 attic/jotblk/requirements.txt  |   2 +
 attic/jotblk/run.sh            |   8 +
 attic/jotblk/static/index.html |   3 +
 attic/jotblk/static/jotblk.js  | 562 +++++++++++++++++++++++++++++++++
 attic/jotblk/static/myforth.fs |  43 +++
 11 files changed, 751 insertions(+)
 create mode 100755 attic/jotblk/Makefile
 create mode 100644 attic/jotblk/README.md
 create mode 100644 attic/jotblk/app.yaml
 create mode 100644 attic/jotblk/dstore.sh
 create mode 100644 attic/jotblk/main.py
 create mode 100644 attic/jotblk/requirements.txt
 create mode 100755 attic/jotblk/run.sh
 create mode 100644 attic/jotblk/static/index.html
 create mode 100644 attic/jotblk/static/jotblk.js
 create mode 100644 attic/jotblk/static/myforth.fs

diff --git a/.gitignore b/.gitignore
index ac12813..39e403e 100644
--- a/.gitignore
+++ b/.gitignore
@@ -1,2 +1,3 @@
 out
 build.ninja
+attic/jotblk/env
diff --git a/attic/jotblk/Makefile b/attic/jotblk/Makefile
new file mode 100755
index 0000000..ef8aaa3
--- /dev/null
+++ b/attic/jotblk/Makefile
@@ -0,0 +1,12 @@
+all:
+	./run.sh
+
+deploy:
+	gcloud app deploy -q --project jotblk *.yaml  
+
+setup:
+	python3 -m venv env
+	env/bin/pip install -r requirements.txt
+
+datastore:
+	echo "Run: . dstore.sh"
diff --git a/attic/jotblk/README.md b/attic/jotblk/README.md
new file mode 100644
index 0000000..bcf92f5
--- /dev/null
+++ b/attic/jotblk/README.md
@@ -0,0 +1,20 @@
+# jotblk
+
+A web based block based editor to run on AppEngine.
+
+To run you need the AppEngine SDK.
+
+To setup run:
+```
+make setup
+```
+
+In parallel run (for the datastore):
+```
+. dstore.sh
+```
+
+And separately (to run a webserver on http://localhost:8080):
+```
+./run.sh
+```
diff --git a/attic/jotblk/app.yaml b/attic/jotblk/app.yaml
new file mode 100644
index 0000000..0b6195f
--- /dev/null
+++ b/attic/jotblk/app.yaml
@@ -0,0 +1,17 @@
+runtime: python39
+
+default_expiration: "10m"
+
+handlers:
+- url: /
+  static_files: static/index.html
+  upload: static/index.html
+  secure: always
+
+- url: /static
+  static_dir: static
+  secure: always
+
+- url: /io
+  script: main.app
+  secure: always
diff --git a/attic/jotblk/dstore.sh b/attic/jotblk/dstore.sh
new file mode 100644
index 0000000..c37bab5
--- /dev/null
+++ b/attic/jotblk/dstore.sh
@@ -0,0 +1,2 @@
+# Run this to start an datastore emulator.
+gcloud emulators firestore start --database-mode=datastore-mode --project=jotblk --host-port=127.0.0.1:8099
diff --git a/attic/jotblk/main.py b/attic/jotblk/main.py
new file mode 100644
index 0000000..3521040
--- /dev/null
+++ b/attic/jotblk/main.py
@@ -0,0 +1,81 @@
+# Copyright 2025 Bradley D. Nelson
+#
+# Licensed under the Apache License, Version 2.0 (the "License");
+# you may not use this file except in compliance with the License.
+# You may obtain a copy of the License at
+#
+#     http://www.apache.org/licenses/LICENSE-2.0
+#
+# Unless required by applicable law or agreed to in writing, software
+# distributed under the License is distributed on an "AS IS" BASIS,
+# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+# See the License for the specific language governing permissions and
+# limitations under the License.
+
+import base64
+from flask import Flask, request, send_from_directory
+from google.cloud import datastore
+
+client = datastore.Client()
+
+root_passwd_key = client.key('passwd', 'root')
+root_passwd_entity = client.get(root_passwd_key)
+if root_passwd_entity is None:
+  root_passwd = 'xyzzy'
+else:
+  root_passwd = root_passwd_entity['secret']
+
+def SaveBlock(index, data):
+  assert index >= 0
+  assert len(data) == 1024, len(data)
+  entity = datastore.Entity(key=client.key('block', index+1))
+  entity.update({'data': data})
+  client.put(entity)
+  return ''
+
+def LoadBlocks(start, end):
+  assert end >= end
+  assert start >= 0
+  assert end - start <= 128
+  query = client.query(kind='block')
+  first_key = client.key('block', start+1)
+  last_key = client.key('block', end+1)
+  query.key_filter(first_key, '>=')
+  query.key_filter(last_key, '<')
+  entities = query.fetch()
+  blks = {}
+  for i in entities:
+    blks[i.key.path[0]['id']-1] = i['data']
+  result = []
+  for i in range(start, end+1):
+    if i in blks:
+      result.append(blks[i])
+    else:
+      result.append(b' ' * 1024)
+  return b''.join(result) 
+
+app = Flask(__name__)
+
+@app.route('/<path:filename>')
+def canned(filename):
+  return send_from_directory('static', filename)
+
+@app.route('/')
+def root():
+  return canned('index.html')
+
+@app.route('/io', methods=['POST'])
+def io():
+  if root_passwd != request.form['passwd']:
+    return 'deny', 403
+  if request.form['command'] == 'read':
+    start = int(request.form['start'])
+    end = int(request.form['end'])
+    return LoadBlocks(start, end)
+  elif request.form['command'] == 'write':
+    index = int(request.form['index'])
+    data = request.files['data'].read()
+    return SaveBlock(index, data)
+
+if __name__ == '__main__':
+  app.run(host='127.0.0.1', port=8080, debug=True)
diff --git a/attic/jotblk/requirements.txt b/attic/jotblk/requirements.txt
new file mode 100644
index 0000000..13f13f5
--- /dev/null
+++ b/attic/jotblk/requirements.txt
@@ -0,0 +1,2 @@
+Flask==3.0.0
+google-cloud-datastore==2.15.1
diff --git a/attic/jotblk/run.sh b/attic/jotblk/run.sh
new file mode 100755
index 0000000..b9bbc2e
--- /dev/null
+++ b/attic/jotblk/run.sh
@@ -0,0 +1,8 @@
+#! /bin/bash
+
+export DATASTORE_DATASET=jotblk
+export DATASTORE_EMULATOR_HOST=127.0.0.1:8099
+export DATASTORE_EMULATOR_HOST_PATH=127.0.0.1:8099/datastore
+export DATASTORE_HOST=http://127.0.0.1:8099
+export DATASTORE_PROJECT_ID=jotblk
+env/bin/python3 main.py
diff --git a/attic/jotblk/static/index.html b/attic/jotblk/static/index.html
new file mode 100644
index 0000000..28144c2
--- /dev/null
+++ b/attic/jotblk/static/index.html
@@ -0,0 +1,3 @@
+<!DOCTYPE html>
+<body>
+<script src="jotblk.js"></script>
diff --git a/attic/jotblk/static/jotblk.js b/attic/jotblk/static/jotblk.js
new file mode 100644
index 0000000..708a897
--- /dev/null
+++ b/attic/jotblk/static/jotblk.js
@@ -0,0 +1,562 @@
+// Copyright 2025 Bradley D. Nelson
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//     http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+'use strict';
+
+const MAX_BLOCKS = 16 * 1024;
+const SYNC_CHUNK = 64;
+const DIRTY = 1;
+const LOADED = 2;
+var blocks = new Uint8Array(1024 * MAX_BLOCKS);
+var flags = new Uint8Array(MAX_BLOCKS);
+var clipboard = [];
+var screen_history = [];
+var keymap = {};
+var scr = 0;
+var pos = 0;
+var marker = 0;
+var passwd = '';
+var ForthKeyDown = null;
+var ForthKeyPress = null;
+var forth_added = false;
+var ueforth = null;
+
+document.body.style.overflow = 'hidden';
+document.body.style.margin = '0';
+document.body.style.border = '0';
+document.body.style.padding = '0';
+var canvas = document.createElement('canvas');
+document.body.appendChild(canvas);
+var ctx = canvas.getContext('2d');
+
+function SpaceIt() {
+  if (!(flags[scr] & LOADED)) {
+    return;
+  }
+  if (blocks[scr * 1024] == 0) {
+    for (var i = 0; i < 1024; ++i) {
+      blocks[i + scr * 1024] = 32;
+    }
+    flags[scr] |= DIRTY;
+  }
+}
+
+function IsEmpty(n) {
+  for (var i = 0; i < 1024; i++) {
+    var ch = blocks[i + n * 1024];
+    if (ch != 32 && ch != 0) {
+      return false;
+    }
+  }
+  return true;
+}
+
+function FindEnd() {
+  var i = pos;
+  while (i < 1023 &&
+         (blocks[scr * 1024 + i] != 32 ||
+          blocks[scr * 1024 + i + 1] != 32)) {
+    i++;
+  }
+  return i;
+}
+
+function Insert() {
+  var end = FindEnd();
+  for (var i = end; i >= pos; i--) {
+    blocks[scr * 1024 + i + 1] = blocks[scr * 1024 + i];
+  }
+  blocks[scr * 1024 + pos] = 32;
+  flags[scr] |= DIRTY;
+}
+
+function Delete() {
+  var end = FindEnd();
+  for (var i = pos; i < end; i++) {
+    blocks[scr * 1024 + i] = blocks[scr * 1024 + i + 1];
+  }
+  flags[scr] |= DIRTY;
+}
+
+function FindSpan() {
+  var i = Math.floor(pos / 64) * 64;
+  var min = 63;
+  var max = 0;
+  for (var j = 0; j < 64; j++) {
+    if (blocks[scr * 1024 + i + j] != 32) {
+      min = Math.min(min, j);
+      max = Math.max(max, j);
+    }
+  }
+  if (min > max) {
+    return [i, i + 63];
+  }
+  return [i + min, i + max];
+}
+
+function Home() {
+  var span = FindSpan();
+  var start = Math.floor(pos / 64) * 64;
+  if (pos == span[0]) {
+    pos = start;
+  } else {
+    pos = span[0];
+  }
+}
+
+function End() {
+  var span = FindSpan();
+  var end = Math.floor(pos / 64) * 64 + 63;
+  var span1 = Math.min(span[1] + 1, end);
+  if (pos == span1) {
+    pos = end;
+  } else {
+    pos = span1;
+  }
+}
+
+function Up() {
+  if (pos >= 64) {
+    pos -= 64;
+  }
+}
+
+function Down() {
+  if (pos + 64 < 1024) {
+    pos += 64;
+  }
+}
+
+function Left() {
+  pos = Math.max(0, pos - 1);
+}
+
+function Right() {
+  pos = Math.min(1023, pos + 1);
+}
+
+function Copy() {
+  var row = Math.floor(pos / 64) * 64;
+  clipboard.push(blocks.slice(scr * 1024 + row, scr * 1024 + row + 64));
+  Up();
+}
+
+function Cut() {
+  var row = Math.floor(pos / 64) * 64;
+  clipboard.push(blocks.slice(scr * 1024 + row, scr * 1024 + row + 64));
+  for (var j = 0; j < 64; j++) {
+    blocks[scr * 1024 + row + j] = 32;
+  }
+  flags[scr] |= DIRTY;
+  Up();
+}
+
+function Paste() {
+  if (clipboard.length == 0) {
+    return;
+  }
+  var row = Math.floor(pos / 64) * 64;
+  var data = clipboard.pop();
+  for (var j = 0; j < 64; j++) {
+    blocks[scr * 1024 + row + j] = data[j];
+  }
+  flags[scr] |= DIRTY;
+  Down();
+}
+
+function Update() {
+  SpaceIt();
+  ctx.fillStyle = 'black';
+  ctx.fillRect(0, 0, canvas.width, canvas.height);
+  ctx.font = '16px consolas, Monaco, monospace';
+  ctx.textAlign = 'center';
+  ctx.textBaseline = 'middle';
+  ctx.save();
+  ctx.scale(canvas.width / 64 , canvas.height / 17);
+  for (var j = 0; j < 16; ++j) {
+    for (var i = 0; i < 64; ++i) {
+      if (pos === i + j * 64) {
+        ctx.fillStyle = '#750';
+        ctx.fillRect(i, j, 1, 1);
+      }
+    }
+  }
+  ctx.save();
+  var m = ctx.measureText('W');
+  var w = m.width;
+  var h = m.fontBoundingBoxAscent + m.fontBoundingBoxDescent;
+  ctx.scale(1 / w, 1 / h);
+  for (var j = 0; j < 16; ++j) {
+    for (var i = 0; i < 64; ++i) {
+      var ch = String.fromCharCode(blocks[i + j * 64 + scr * 1024]);
+      ctx.fillStyle = '#fb0';
+      ctx.fillText(ch, (i + 0.5) * w, (j + 0.5) * h);
+    }
+  }
+  ctx.fillStyle = '#750';
+  ctx.textAlign = 'right';
+  var info = '';
+  if (flags[scr] & DIRTY) {
+    info += 'D ';
+  }
+  if (!(flags[scr] & LOADED)) {
+    info += 'L ';
+  }
+  info += scr;
+  ctx.fillText(info, 63.5 * w, 16.5 * h);
+  ctx.restore();
+  ctx.restore();
+}
+
+function LoadChunk(n) {
+  if ((flags[n * SYNC_CHUNK] & LOADED)) {
+    return Promise.resolve();
+  } else {
+    return LoadBlocks(n * SYNC_CHUNK, (n + 1) * SYNC_CHUNK).then(function() {
+      Update();
+    });
+  }
+}
+
+function MaybeLoad() {
+  var s = Math.floor(scr / SYNC_CHUNK);
+  return LoadChunk(s);
+}
+
+function LineString(blk, row) {
+  var result = '';
+  for (var col = 0; col < 64; col++) {
+    result += String.fromCharCode(blocks[blk * 1024 + row * 64 + col]);
+  }
+  return result;
+}
+
+function BlockString(blk, linebreaks) {
+  var result = '';
+  for (var row = 0; row < 16; row++) {
+    result += LineString(blk, row);
+    if (linebreaks) {
+      result += '\n';
+    }
+  }
+  return result;
+}
+
+function Eval(n) {
+  eval(BlockString(n, true));
+}
+
+function Print() {
+  var start = Math.min(marker, scr);
+  var end = Math.max(marker, scr);
+  var content = '';
+  content += '<!DOCTYPE html>\n';
+  for (var i = start; i <= end; i++) {
+    content += '<pre style="border: 1px solid; display: inline-block;">\n';
+    content += BlockString(i, true);
+    content += '<hr/>' + i;
+    content += '</pre><br/>\n';
+  }
+  var blob = new Blob([content], { type: 'text/html' });
+  var url = URL.createObjectURL(blob);
+  window.open(url, '_blank');
+}
+
+function Backspace() {
+  if (pos > 0) {
+    --pos;
+    Delete();
+  }
+}
+
+function Goto(n) {
+  scr = n;
+  MaybeLoad();
+}
+
+function Gosub(n) {
+  screen_history.push(scr);
+  Goto(n);
+}
+
+function Adjust(n) {
+  Goto(Math.max(0, Math.min(MAX_BLOCKS - 1, scr + n)));
+}
+
+function Enter() {
+  pos = Math.floor((pos + 64) / 64) * 64;
+  if (pos > 1023) {
+    pos -= 64;
+  }
+}
+
+function ShiftUp() {
+  pos = (pos % 64);
+}
+
+function ShiftDown() {
+  pos = (pos % 64) + 15 * 64;
+}
+
+function GetLink() {
+  var s = BlockString(scr, false);
+  var at = s.indexOf('@', pos);
+  var paren = s.indexOf(' )', pos);
+  if (at >= 0 && (at < paren || paren < 0)) {
+    return s.slice(at).split(' ')[0];
+  }
+  if (paren >= 0) {
+    var p2 = s.lastIndexOf('( ', paren);
+    if (p2 >= 0) {
+      return s.slice(p2, paren + 2);
+    }
+  }
+  return '';
+}
+
+function Find(s) {
+  for (var i = 0; i < MAX_BLOCKS; i++) {
+    var j = (scr + 1 + i) % MAX_BLOCKS;
+    if (BlockString(j, false).indexOf(s) >= 0) {
+      return j;
+    }
+  }
+  return null;
+}
+
+function FollowLink() {
+  var link = GetLink();
+  if (link.startsWith('@')) {
+    var n = parseInt(link.slice(1));
+    Gosub(n);
+  } else if (link.startsWith('( ')) {
+    var n = Find(link.slice(2, -2));
+    if (n !== null) {
+      Gosub(n);
+    }
+  }
+}
+
+function Type(ch) {
+  Insert();
+  blocks[pos + scr * 1024] = ch;
+  pos = Math.min(1023, pos + 1);
+}
+
+function Key(e) {
+  if (e.ctrlKey && keymap['^' + e.key]) {
+    keymap['^' + e.key](e);
+  } else if (e.shiftKey && keymap['+' + e.key]) {
+    keymap['+' + e.key](e);
+  } else if (keymap[e.key]) {
+    keymap[e.key](e);
+  } else if (e.key.length == 1 && !e.ctrlKey) {
+    Type(e.key.charCodeAt(0));
+  } else {
+    return true;
+  }
+  Update();
+  e.preventDefault();
+  return false;
+}
+
+function Login(e) {
+  if (e.key == 'Backspace') {
+    passwd = passwd.slice(0, -1);
+  } else if (e.key == 'Enter') {
+    window.onkeydown = Key;
+    MaybeLoad().then(function() {
+      Eval(63);
+    });
+  } else if (e.key.length == 1) {
+    passwd += e.key;
+  }
+  Update();
+  e.preventDefault();
+  return false;
+}
+
+function Resize() {
+  canvas.width = window.innerWidth;
+  canvas.height = window.innerHeight;
+  Update();
+}
+
+function SaveBlock(i) {
+  var fd = new FormData();
+  fd.append('command', 'write');
+  fd.append('passwd', passwd);
+  fd.append('index', i);
+  fd.append('data', new Blob([blocks.slice(i * 1024, (i + 1) * 1024)],
+                             {type: "application/octet-stream"}));
+  return fetch('/io', {'method': 'POST', body: fd}).then(function() {
+    flags[i] &= ~DIRTY;
+    Update();
+  });
+}
+
+function Sync() {
+  for (var i = 0; i < MAX_BLOCKS; ++i) {
+    if ((flags[i] & LOADED) && (flags[i] & DIRTY)) {
+      SaveBlock(i);
+    }
+  }
+}
+
+function FindEmpty() {
+  screen_history.push(scr);
+  while (!IsEmpty(scr)) {
+    Adjust(1);
+  }
+}
+
+function StampLog() {
+  var now = new Date();
+  var month = ('0' + (1 + now.getMonth())).slice(-2);
+  var day = ('0' + now.getDate()).slice(-2);
+  var dt = now.getFullYear() + '-' + month + '-' + day;
+  for (var i = 0; i < dt.length; i++) {
+    blocks[54 + i + scr * 1024] = dt.charCodeAt(i);
+  }
+  var mark = 'LOG: ';
+  for (var i = 0; i < mark.length; i++) {
+    blocks[i + scr * 1024] = mark.charCodeAt(i);
+  }
+  pos = mark.length;
+  flags[scr] |= DIRTY;
+}
+
+function Back() {
+  if (screen_history.length) {
+    Goto(screen_history.pop());
+  }
+}
+
+function LoadBlocks(start, end) {
+  var fd = new FormData();
+  fd.append('command', 'read');
+  fd.append('passwd', passwd);
+  fd.append('start', start);
+  fd.append('end', end);
+  return fetch('/io', {'method': 'POST', body: fd}).then(function(response) {
+    if (!response.ok) {
+      throw 'bad fetch';
+    }
+    return response.arrayBuffer().then(function(data) {
+      var u8 = new Uint8Array(data);
+      if (u8.length != (end + 1 - start) * 1024) {
+        throw 'bad load';
+      }
+      for (var i = start; i < end; i++) {
+        if (flags[i] & LOADED) {
+          return;
+        }
+        var dst = i * 1024;
+        var src = (i - start) * 1024;
+        for (var j = 0; j < 1024; j++) {
+          blocks[j + dst] = u8[j + src];
+        }
+        flags[i] |= LOADED;
+      }
+    });
+  });
+}
+
+function ForthKeyFilter(e) {
+  if (e.key == 'f' && e.ctrlKey) {
+    ToggleForth();
+    e.preventDefault();
+    return false;
+  }
+  return ForthKeyDown(e);
+}
+
+function ToggleForth() {
+  if (!forth_added) {
+    forth_added = true;
+    var fscript = document.createElement('script');
+    fscript.src = 'myforth.fs';
+    fscript.type = 'text/forth';
+    document.body.appendChild(fscript);
+    var script = document.createElement('script');
+    script.src = 'https://eforth.appspot.com/ueforth.js';
+    document.body.appendChild(script);
+    function Loader() {
+      if (ueforth !== null) {
+        ueforth.Start();
+        canvas.style.display = 'none';
+        setTimeout(function() {
+          ForthKeyDown = window.onkeydown;
+          ForthKeyPress = window.onkeypress;
+          window.onkeydown = ForthKeyFilter;
+        }, 500);
+      } else {
+        setTimeout(Loader, 10);
+      }
+    }
+    Loader();
+    return;
+  }
+  if (window.onkeydown === Key) {
+    window.onkeydown = ForthKeyFilter;
+    window.onkeypress = ForthKeyPress;
+    canvas.style.display = 'none';
+    ueforth.screen.style.display = '';
+  } else {
+    window.onkeydown = Key;
+    window.onkeypress = null;
+    ueforth.screen.style.display = 'none';
+    canvas.style.display = '';
+    Resize();
+  }
+}
+
+function Init() {
+  keymap['Delete'] = Delete;
+  keymap['Backspace'] = Backspace;
+  keymap['PageUp'] = function() { Adjust(-1); };
+  keymap['PageDown'] = function() { Adjust(1); };
+  keymap['+PageUp'] = function() { Adjust(-16); };
+  keymap['+PageDown'] = function() { Adjust(16); };
+  keymap['Home'] = Home;
+  keymap['End'] = End;
+  keymap['Enter'] = Enter;
+  keymap['^Enter'] = FollowLink;
+  keymap['ArrowUp'] = Up;
+  keymap['ArrowDown'] = Down;
+  keymap['ArrowLeft'] = Left;
+  keymap['ArrowRight'] = Right;
+  keymap['+ArrowUp'] = ShiftUp;
+  keymap['+ArrowDown'] = ShiftDown;
+  keymap['+ArrowLeft'] = Home;
+  keymap['+ArrowRight'] = End;
+  keymap['^c'] = Copy;
+  keymap['^x'] = Cut;
+  keymap['^v'] = Paste;
+  keymap['^m'] = function() { marker = scr; };
+  keymap['^p'] = Print;
+  keymap['^g'] = function() { Eval(scr); };
+  keymap['^o'] = FindEmpty;
+  keymap['^l'] = StampLog;
+  keymap['^b'] = Back;
+  keymap['^f'] = ToggleForth;
+  keymap['^h'] = function() { Gosub(0); };
+
+  window.addEventListener('resize', Resize);
+  window.onkeydown = Login;
+  Resize();
+}
+Init();
+
+setInterval(Sync, 3000);
diff --git a/attic/jotblk/static/myforth.fs b/attic/jotblk/static/myforth.fs
new file mode 100644
index 0000000..9eb97df
--- /dev/null
+++ b/attic/jotblk/static/myforth.fs
@@ -0,0 +1,43 @@
+\ Copyright 2021 Bradley D. Nelson
+\
+\ Licensed under the Apache License, Version 2.0 (the "License");
+\ you may not use this file except in compliance with the License.
+\ You may obtain a copy of the License at
+\
+\     http://www.apache.org/licenses/LICENSE-2.0
+\
+\ Unless required by applicable law or agreed to in writing, software
+\ distributed under the License is distributed on an "AS IS" BASIS,
+\ WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+\ See the License for the specific language governing permissions and
+\ limitations under the License.
+
+web definitions
+
+JSWORD: block-read { n a -- }
+  for (var i = 0; i < 1024; i++) {
+    u8[a + i] = blocks[n * 1024 + i];
+  }
+~
+
+also internals
+
+create block-buffer 1024 allot
+
+also forth definitions
+
+variable scr
+: block ( n -- a ) block-buffer block-read block-buffer ;
+: buffer ( n -- a ) block ;
+
+only forth definitions
+
+( Loading )
+: load ( n -- ) block 1024 evaluate ;
+: thru ( a b -- ) over - 1+ for aft dup >r load r> 1+ then next drop ;
+
+( Listing )
+: list ( n -- ) scr ! ." Block " scr @ . cr scr @ block
+   15 for dup 63 type [char] | emit space 15 r@ - . cr 64 + next drop ;
+
+only forth definitions