Tromp Diagrams

multi-pane lambda calculus visualizer

Each pane is independent. Click + to add another. Use Sync in the toolbar to step / run all panes together — useful for comparing reduction strategies side-by-side. Multiline input is on by default (Ctrl+Enter to draw, Enter for newline). Long λ-bodies can be folded with the ⌄ button on each pane.

Settings

Toolbar 0 / 6

Click the pin on a row to add or remove it from the global toolbar. Order in the toolbar follows the order you pin.

Diagram scaleHow thick the diagram lines render.

8px

Animation speedHow fast reductions play. Doesn't affect god mode.

1.0x

Display

Color-code variablesTint each bound variable so reductions are easier to follow. Animate transitionsSmoothly morph lines between β-reductions instead of snapping. Show explicit parenthesesRender every grouping in the pretty-printed code, not just the necessary ones.

Layout

Side-by-side panesStack panes horizontally for comparison instead of vertically. Hide Definitions sidebarGive the diagram the full page width — useful for screenshots or narrow screens.

Editor

Disable autocompleteStop suggesting matching definition names while you type.

Reduction defaults

Default strategyNew panes start with this reduction strategy selected.

Default max stepsRun / Run N stops here. Leave blank or 0 for unlimited.

Show BLC encoding by defaultPre-open the binary lambda calculus row on every new pane. Show Recognize by defaultPre-open the known-term recognition row on every new pane.

Advanced

Sync modeStep / Run / Reset apply to every pane at once. Sync buttons appear in the toolbar. God modeStrips out the diagram, pretty-printer, and most controls. Run blasts through reductions at full speed and only displays the final result — for large terms where the animation gets in the way. Show record button BETAReveal a ● Rec button on each pane to capture reductions as webm. Frame timing is rough — diagrams with many steps may stutter.

Keyboard shortcuts

Editor

Ctrl+Enter: Draw the current expression
Enter: Newline (expression spans multiple lines)
Tab: Accept the highlighted autocomplete suggestion
↑ / ↓: Navigate autocomplete
Esc: Close autocomplete or find bar

Find / replace

Ctrl+F: Open find bar in the active pane
Esc: Close the find bar

View

Esc: Exit fullscreen / presentation
Mouse wheel: Zoom in / out at cursor
Click + drag: Pan diagram

Presentation mode (▶ Present)

Space / →: Step forward
←: Step back
R: Run
P: Pause / resume
0: Reset
F: Fit diagram to viewport
H: Hide HUD & code overlay

This dialog

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