Textly

Expression Block

The Expression block in Open Roberta Lab allows users to write complex expressions directly in text format using the TextlyJava language, enhancing the versatility of programming in Open Roberta Lab.

To access the Expression block in Open Roberta Lab, press Ctrl + 4 (or Strg + 4 for German keyboards).Once the block appears, users can write any expression and either generate the corresponding code or run a simulation using the available options in Open Roberta Lab.

The Expression block includes a combo box that allows users to select the appropriate data type for their expression. The available data types depend on the robot being used. For example, for the Microbitv2, users can choose from specific options tailored to that device. Selecting the correct data type ensures compatibility with other blocks and operations in Open Roberta Lab.

Example:

Consider the mathematical expression:

$$ c = \sqrt{a^2 + b^2 - 2ab \cdot \cos(\gamma)} $$

While this expression could be represented using multiple NEPO blocks, using the Expression block allows for a faster textual representation:

sqrt(a^2 + b^2 - 2*a*b * cos(gamma))

For example, given:

a = 5
b = 7
gamma = $$\frac{\pi}{3} $$

To compute the value of ( c ) using the Law of Cosines, the corresponding NEPO program representation is as follows: block_2 When utilizing the EvalExpr block for a textual expression, the representation of the equation is:

block_3

TextlyJava Expression Language Guide

TextlyJava is a flexible expression language used for programming robots and handling a variety of tasks like arithmetic operations, logic, image manipulations, and robot-specific commands. This guide will introduce how to use various types of expressions supported by TextlyJava.

Expressions Overview

Expressions in TextlyJava represent programmable blocks of various types, such as:

Numbers
Strings
Booleans
Connections
Colors
Images
Arrays of these types

Each expression can perform arithmetic, logical operations, and string manipulations, with specialized expressions for specific robots.

General Expressions:

Logic Expressions

Block (Image)	Textly Representation	Example
	`expr && expr`	`a && b`
	`expr \|\| expr`	`a \|\| b`
	`expr == expr`	`a == b`
	`expr != expr`	`a != b`
	`expr > expr`	`a > b`
	`expr < expr`	`a < b`
	`expr >= expr`	`a >= b`
	`expr <= expr`	`a <= b`
	`expr ? expr : expr`	`a == b ? x : y`
	`!expr`	`!a`
	`true`	`true`
	`false`	`false`
	`null`	`null`

Mathematical and Function Expressions

Block (Image)	Textly Representation	Example
	`expr + expr`	`a + b`
	`expr - expr`	`a - b`
	`expr * expr`	`a * b`
	`expr / expr`	`a / b`
	`expr ^ expr`	`a ^ b`
	`expr % expr`	`a % b`
	`- expr`	`-a`
	`sin(expr)`	`sin(90)`
	`cos(expr)`	`cos(90)`
	`tan(expr)`	`tan(45)`
	`asin(expr)`	`asin(1)`
	`acos(expr)`	`acos(1)`
	`atan(expr)`	`atan(1)`
	`exp(expr)`	`exp(1)`
	`square(expr)`	`square(2)`
	`sqrt(expr)`	`sqrt(4)`
	`abs(expr)`	`abs(-10)`
	`log10(expr)`	`log10(100)`
	`log(expr)`	`log(10)`
	`randomInt(expr, expr)`	`randomInt(1, 100)`
	`randomFloat()`	`randomFloat()`
	`randomItem(ListExpression)`	`randomItem(ListExpression)`
	`floor(expr)`	`floor(3.14)`
	`ceil(expr)`	`ceil(3.14)`
	`round(expr)`	`round(3.5)`
	`isEven(expr)`	`isEven(2)`
	`isOdd(expr)`	`isOdd(3)`
	`isPrime(expr)`	`isPrime(7)`
	`isWhole(expr)`	`isWhole(3)`
	`isPositive(expr)`	`isPositive(10)`
	`isNegative(expr)`	`isNegative(-5)`
	`isDivisibleBy(expr, expr)`	`isDivisibleBy(10, 5)`
	`sum(ListExpression)`	`sum(ListExpression)`
	`max(ListExpression)`	`max(ListExpression)`
	`min(ListExpression)`	`min(ListExpression)`
	`average(ListExpression)`	`average(ListExpression)`
	`median(ListExpression)`	`median(ListExpression)`
	`stddev(ListExpression)`	`stddev(ListExpression)`
	`constrain(expr, expr, expr)`	`constrain(50, 0, 100)`
	`castToString(expr)`	`castToString(123)`
	`castToChar(expr)`	`castToChar(65)`
	`phi`	`phi`
	`pi`	`pi`
	`e`	`e`
	`sqrt2`	`sqrt2`
	`sqrt_1_2`	`sqrt_1_2`
	`inf`	`inf`

Clarification:

ListExpression: In all examples where ListExpression is used, it refers to a predefined list of numbers. In TextlyJava, you can only work with predefined lists, so you need to define ListExpression beforehand. An example of a predefined list could be:

textly ListExpression = [1, 2, 3, 4, 5]

Text Expressions

Block (Image)	Textly Representation	Example
	`"String"`	`"Hello World"`
	`createTextWith(expr, expr, ...)`	`createTextWith("Hello", " ", "World")`
	`castToNumber(expr)`	`castToNumber("123")`
	`castStringToNumber(expr)`	`castStringToNumber("HelloWorld", 1)`

List Expressions

Block (Image)	Textly Representation	Example
	`[expr, expr, ...]`	`[1, 2, 3, 4, 5]`
	`createListWith(expr, expr, ...)`	`createListWith(1, 5)`
	`createEmptyList(Type of list)`	`createEmptyList(Number)`
	`size(ListExpression)`	`size(ListExpression)`
	`isEmpty(ListExpression)`	`isEmpty(ListExpression)`
	`indexOfFirst(ListExpression, expr)`	`indexOfFirst(ListExpression, 2)`
	`indexOfLast(ListExpression, expr)`	`indexOfLast(ListExpression, 3)`
	`get(ListExpression, index)`	`get(ListExpression, 0)`
	`getFromEnd(ListExpression, index)`	`getFromEnd(ListExpression, 1)`
	`getFirst(ListExpression)`	`getFirst(ListExpression)`
	`getLast(ListExpression)`	`getLast(ListExpression)`
	`getAndRemove(ListExpression, index)`	`getAndRemove(ListExpression, 1)`
	`getAndRemoveFromEnd(ListExpression, index)`	`getAndRemoveFromEnd(ListExpression, 1)`
	`getAndRemoveFirst(ListExpression)`	`getAndRemoveFirst(ListExpression)`
	`getAndRemoveLast(ListExpression)`	`getAndRemoveLast(ListExpression)`
	`subList(ListExpression, from, to)`	`subList(ListExpression, 1, 3)`
	`subListFromIndexToLast(ListExpression, index)`	`subListFromIndexToLast(ListExpression, 1)`
	`subListFromIndexToEnd(ListExpression, index)`	`subListFromIndexToEnd(ListExpression, 1)`
	`subListFromFirstToIndex(ListExpression, index)`	`subListFromFirstToIndex(ListExpression, 1)`
	`subListFromFirstToLast(ListExpression)`	`subListFromFirstToLast(ListExpression)`
	`subListFromFirstToEnd(ListExpression)`	`subListFromFirstToEnd(ListExpression)`
	`subListFromEndToIndex(ListExpression, index)`	`subListFromEndToIndex(ListExpression, 1)`
	`subListFromEndToEnd(ListExpression, index)`	`subListFromEndToEnd(ListExpression, 1)`
	`subListFromEndToLast(ListExpression, index)`	`subListFromEndToLast(ListExpression, 1)`

User-Defined Function Call

Block (Image)	Textly Representation	Example
	`functionName(expr, expr, ...)`	`myFunction(0, 0)`

Specific Robot Expressions

MicrobitV2

Block (Image)	Textly Representation	Example
	`image(ImageName)` _{ImageName options: heart, heartSmall, happy, smile, sad, confused, angry, asleep, surprised, silly, fabulous, meh, yes, no, triangle, triangleLeft, chessboard, diamond, diamondSmall, squareBig, squareSmall, rabbit, cow, musicCrotchet, musicQuaver, musicQuavers, pitchfork, xmas, pacman, target, tshirt, rollerskate, duck, house, tortoise, butterfly, stickFigure, ghost, sword, giraffe, skull, umbrella, snake}	`image(heart)`
	`image.define(Image defined by the user)`	`image.define([ [0, 0, 0, 0, #], [0, 0, 0, 0, #], [0, 0, 0, 0, #], [0, 0, 0, 0, #], [0, 0, 0, 0, #] ])`
	`image.shift(Direction, expr, expr)` Direction options: up, down, left, right	`image.shift(left, 2, 3)`
	`image.invert(expr)`	`image.invert(image)`
	`microbitv2.accelerometerSensor(Slot)` Slot options: x, y, z, strength	`microbitv2.accelerometerSensor(x)`
	`microbitv2.logoTouchSensor.isPressed()`	`microbitv2.logoTouchSensor.isPressed()`
	`microbitv2.compassSensor.getAngle()`	`microbitv2.compassSensor.getAngle()`
	`microbitv2.gestureSensor.currentGesture(Gesture)` Gesture options: up, down, faceDown, faceUp, shake, freefall	`microbitv2.gestureSensor.currentGesture(shake)`
	`microbitv2.keysSensor.isPressed(Button)` Button options: Defined in robot configuration	`microbitv2.keysSensor.isPressed(A)`
	`microbitv2.lightSensor.getLevel()`	`microbitv2.lightSensor.getLevel()`
	`microbitv2.pinGetValueSensor(Pin, Mode)` Pin: Defined in robot configuration Mode options: analog, digital, pulseHigh, pulseLow	`microbitv2.pinGetValueSensor(P0, analog)`
	`microbitv2.pinTouchSensor.isPressed(INT)`	`microbitv2.pinTouchSensor.isPressed(1)`
	`microbitv2.soundSensor.microphone.soundLevel()`	`microbitv2.soundSensor.microphone.soundLevel()`
	`microbitv2.temperatureSensor()`	`microbitv2.temperatureSensor()`
	`microbitv2.timerSensor()`	`microbitv2.timerSensor()`
	`microbitv2.getLedBrightness(expr, expr)`	`microbitv2.getLedBrightness(1, 2)`
	`microbitv2.receiveMessage(DataType)` DataType options: Number, Boolean, String	`microbitv2.receiveMessage(Number)`

WeDo

Block (Image)	Textly Representation	Example
	`#color` Color options: `#pink`, `#purple`, `#blue`, `#green`, `#lightgreen`, `#yellow`, `#orange`, `#red`, `#white`, `#rgb(XXXXXX)`	`#green`, `#rgb(008000)`
	`wedo.gyroSensor.isTilted(port, direction)` Port options: Defined in robot configuration Direction options: `up`, `down`, `back`, `front`, `no`, `any`	`wedo.gyroSensor.isTilted(port1, front)`
	`wedo.infraredSensor(port)` Port options: Defined in robot configuration	`wedo.infraredSensor(port2)`
	`wedo.keysSensor.isPressed(button)` Button options: Defined in robot configuration	`wedo.keysSensor.isPressed(button1)`
	`timerSensor()`	`timerSensor()`

Ev3

Block (Image)	Textly Representation	Example
	`#rgb(hex)` or `#colorName` Colors: `#rgb(0057a6)` or `#blue`, `#rgb(585858)` or `#gray`, `#rgb(000000)` or `#black`, `#rgb(f7d117)` or `#yellow`, `#rgb(00642e)` or `#green`, `#rgb(b30006)` or `#red`, `#rgb(FFFFFF)` or `#white`, `#rgb(532115)` or `#brown`	`#rgb(0057a6)` `#rgb(f7d117)`
	`ev3.connectToRobot(expr)`	`ev3.connectToRobot("weDo")`
	`ev3.receiveMessage(expr)`	`ev3.receiveMessage(null)`
	`ev3.waitForConnection()`	`ev3.waitForConnection()`
	`ev3.getSpeedMotor(port)` Port options: `A`, `B`, `C`, `D`	`ev3.getSpeedMotor(B)`
	`ev3.getVolume()`	`ev3.getVolume()`
	`ev3.touchSensor.isPressed(port)` Port options: `1`, `2`, `3`, `4`	`ev3.touchSensor.isPressed(1)`
	`ev3.ultrasonicSensor.getDistance(port)` `ev3.ultrasonicSensor.getPresence(port)` Port options: `1`, `2`, `3`, `4`	`ev3.ultrasonicSensor.getDistance(4)` `ev3.ultrasonicSensor.getPresence(4)`
	`ev3.colorSensor(mode, port)` Modes: `colour`, `light`, `ambientlight`, `rgb` Port options: `1`, `2`, `3`, `4`	`ev3.colorSensor(colour, 3)` `ev3.colorSensor(light, 3)`
	`ev3.infraredSensor.getDistance(port)` `ev3.infraredSensor.getPresence(port)` Port options: `1`, `2`, `3`, `4`	`ev3.infraredSensor.getDistance(4)` `ev3.infraredSensor.getPresence(4)`
	`ev3.encoderSensor.getDegree(port)` `ev3.encoderSensor.getRotation(port)` `ev3.encoderSensor.getDistance(port)` Port options: `A`, `B`, `C`, `D`	`ev3.encoderSensor.getDegree(B)` `ev3.encoderSensor.getRotation(B)` `ev3.encoderSensor.getDistance(B)`
	`ev3.keysSensor.isPressed(button)` Buttons: `up`, `down`, `left`, `right`, `escape`, `any`	`ev3.keysSensor.isPressed(up)` `ev3.keysSensor.isPressed(any)`
	`ev3.gyroSensor.getAngle(port)` `ev3.gyroSensor.getRate(port)` Port options: `1`, `2`, `3`, `4`	`ev3.gyroSensor.getAngle(2)` `ev3.gyroSensor.getRate(2)`
	`ev3.timerSensor(port)` Port options: `1`, `2`, `3`, `4`, `5`	`ev3.timerSensor(1)`
	`ev3.soundSensor.getSoundLevel(port)` Port options: `1`, `2`, `3`, `4`	`ev3.soundSensor.getSoundLevel(4)`
	`ev3.hiTechCompassSensor.getAngle(port)` `ev3.hiTechCompassSensor.getCompass(port)` Port options: `1`, `2`, `3`, `4`	`ev3.hiTechCompassSensor.getAngle(4)` `ev3.hiTechCompassSensor.getCompass(4)`
	`ev3.hiTechInfraredSensor.getModulated(port)` `ev3.hiTechInfraredSensor.getUnmodulated(port)` Port options: `1`, `2`, `3`, `4`	`ev3.hiTechInfraredSensor.getModulated(4)` `ev3.hiTechInfraredSensor.getUnmodulated(4)`
	`ev3.hiTechColorSensor(mode, port)` Modes: `colour`, `light`, `ambientlight`, `rgb` Port options: `1`, `2`, `3`, `4`	`ev3.hiTechColorSensor(colour, 3)` `ev3.hiTechColorSensor(rgb, 3)`