diff --git a/commands.js b/commands.js
index f343390..ed46575 100644
--- a/commands.js
+++ b/commands.js
@@ -56,7 +56,9 @@ export var keywords = {
"volume": audioVolume,
"envelope": audioEnvelope,
"speak": audioSpeak,
- "voice": audioVoice
+ "voice": audioVoice,
+ "readkey": readKey,
+ "getkey": getKey
};
function expectParameters(...parameters) {
@@ -803,4 +805,41 @@ export function audioVoice(pitch, rate) {
audio.setVoice(getNumber(pitch), getNumber(rate));
basic.executeStatement();
-}
\ No newline at end of file
+}
+
+export function readKey(identifier) {
+ expectParameters(identifier);
+
+ basic.setStore(identifier, hid.getInputBufferKey());
+
+ basic.executeStatement();
+}
+
+export function getKey(identifier) {
+ expectParameters(identifier);
+
+ var key;
+ var waitKey = function() {
+ basic.setDelayTimeout(
+ setTimeout(function() {
+ if (basic.running) {
+ key = hid.getInputBufferKey();
+ if (key === "") {
+ waitKey();
+ } else {
+ basic.setStore(identifier, key);
+ basic.executeStatement();
+ }
+ }
+ }, 10)
+ );
+ };
+
+ key = hid.getInputBufferKey();
+ if (key !== "") {
+ basic.setStore(identifier, key);
+ basic.executeStatement();
+ } else {
+ waitKey();
+ }
+}
diff --git a/docs/reference/io.md b/docs/reference/io.md
index 4a4ec5d..cf2149d 100644
--- a/docs/reference/io.md
+++ b/docs/reference/io.md
@@ -307,4 +307,60 @@ Gets the colour of the pixel at the position specified by arguments `x` and `y`.
70 print saturation*100; "% saturation"
80 print luminance*100; "% luminance"
-
\ No newline at end of file
+
+
+## `getkey`
+```
+getkey k
+```
+
+Waits for a key and sets `k` to the its key code.
+
+
+Example 1: Show key codes
+
+10 getkey x
+20 print x
+30 goto 10
+
+
+
+
+Example 2: Move turtle
+
+10 cls
+20 print "Use W,A,S,D to move! Hit ESC to stop."
+30 left 90
+40 getkey x
+50 if x = "w"
+60 forward 10
+70 else if x = "s"
+80 backward 10
+90 else if x = "a"
+100 left 10
+110 else if x = "d"
+120 right 10
+130 end
+140 goto 40
+
+
+
+## `readkey`
+```
+readkey k
+```
+
+Like `getkey`, but does not wait for a key. It returns what's already available or else an empty string (`""`).
+
+
+Example
+
+10 readkey x
+20 if x != ""
+30 print x
+40 else
+50 print ".";
+60 end
+70 goto 10
+
+
diff --git a/hid.js b/hid.js
index ca70c6b..17e8920 100644
--- a/hid.js
+++ b/hid.js
@@ -19,6 +19,24 @@ export const inputFormats = {
TEXT: 1
};
+const inputBuffer = [];
+
+function clearInputBuffer() {
+ inputBuffer.length = 0;
+}
+
+function appendInputBufferKey(key) {
+ inputBuffer.push(key);
+}
+
+export function peekInputBufferKey() {
+ return inputBuffer.length !== 0 ? inputBuffer[0] : "";
+}
+
+export function getInputBufferKey() {
+ return inputBuffer.shift() || "";
+}
+
function getCaretFormatColourInsensitive(format) {
switch (format) {
case inputFormats.PROGRAM:
@@ -305,6 +323,8 @@ export function startInput(format = inputFormats.TEXT, relativeRow = term.scroll
}
export function startProgramInput(lineValue = "", immediateEdit = true, relativeRow = term.scrollDelta + term.row, rendering = true) {
+ clearInputBuffer();
+
hidInput.value = lineValue;
var newProgramInput = new Input(inputFormats.PROGRAM, relativeRow, lineValue);
@@ -348,6 +368,8 @@ function dispatchInputEvent(event) {
if (focusedInput != null) {
focusedInput.readKey(event);
+ } else {
+ appendInputBufferKey(event.key);
}
}
diff --git a/syntax.js b/syntax.js
index 18bf72c..5c70c5d 100644
--- a/syntax.js
+++ b/syntax.js
@@ -9,7 +9,7 @@ const RE_NUMERIC_LITERAL_HEX = /(?