Data structures · 9 minutes of curiosity

Hello to every creature.

A for-each loop visits each item in a list, in order. On each trip, its variable holds the next item. You can use that value inside the loop.

Your mission: iteration over a list

Loop through otter, dragon, and robot. Say Hello, otter!, Hello, dragon!, and Hello, robot! using the item variable and join blocks.

Main mission: Hello, otter! → Hello, dragon! → Hello, robot!
▦ BLOCK LAB · made for making

Build it: choose a toolbox category, drag blocks onto the canvas, then snap instructions inside when I press Run. Drop values into matching sockets. Edit words or numbers directly on their blocks.

Waking up the blocks…

Projects are saved on this device when storage is available.

Loading the visual editor…
Inputs Try different values

Inputs give your program information. An “input” block reads a value by its exact name. Task checks use their own values.

From blocks to Python A bridge to your next adventure

Generate real Python from these blocks. The helper functions keep Bit’s messages familiar. Python has its own type rules; the Python trail explains them.

Start a fresh plan?

This replaces the blocks on this canvas. Download your project first if you want to keep a copy.

A little hint, please

The creature variable changes each trip. Join “Hello, ” with creature, then join “!” onto the end.

How do I use these blocks?

Pick a category on the left to see its blocks. Drag a block onto the canvas. Instructions connect in a stack inside “when I press Run”. Rounded value blocks go into sockets. Change a field by selecting the word, number, or dropdown on the block.

Use the canvas zoom controls or Fit blocks if a stack goes out of view. Undo can bring back an accidental change. Disconnected blocks do not run. Your canvas saves here on this device.

Pack this idea for later: Iteration lets the same instructions work on every item in a collection. Explore it in Python →

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