Lenient Switch

A ComfyUI custom node that lets you route any value through a switch while specifying the condition separately from the pass-through source.

Most switch nodes force you to choose a slot based on the same value you forward downstream. Lenient Switch decouples those: each slot has its own optional condition input. If a condition is connected, it decides whether that slot wins; if not, the source itself is used for the test. This makes it easy to gate one signal on the truthiness of another (e.g. "forward the image when the mask is non-empty", "pick a prompt based on a flag").

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Node

• Category: Lenient Switch
• Display name: Lenient Switch
• Class: LenientSwitch

Inputs

Slot	Required	Purpose
source_a	yes	Pass-through source (any type)
source_b, source_c, source_d, source_e	no	Additional pass-through sources
pass_if_a … pass_if_e	no	Per-slot truthiness test (not a CONDITIONING input). If unconnected, the matching source_X is used as the condition

Toggles (required):

Toggle	Default	Effect when ON
treat_zero_as_false	true	Numeric 0 / 0.0 is falsy
treat_empty_string_as_false	true	"" is falsy
evaluate_boolean	true	Booleans use their actual value. When OFF, booleans are always truthy
treat_empty_list_as_false	true	Empty list / tuple is falsy
block_on_all_false	false	When every slot is falsy, emit an ExecutionBlocker on the output socket to stop downstream execution
bypass_unselected	false	Skip evaluating the source_X of slots that can't win, so their upstream chains don't run (see below)

None is always falsy. Values that don't match any falsy rule are truthy.

bypass_unselected (lazy evaluation)

When ON, a slot is skipped — its source_X upstream chain is not executed — only when its pass_if_X is connected and falsy (a guaranteed loser). This is ComfyUI-native lazy evaluation, not an rgthree-style mode change: the skipped nodes simply don't run; they are not visually greyed out.

Slots whose pass_if_X is unconnected are always evaluated. Their condition is the source value itself, which can only be known by running the source, so they can't be skipped ahead of time. If you want a slot's upstream to be bypassable, wire its pass_if_X.

Outputs

Output	Type	Meaning
output	any	The source_X of the first slot whose condition is truthy. None if all slots are falsy (or ExecutionBlocker if block_on_all_false is ON)
matched	BOOLEAN	True if a slot matched, False otherwise (always False when all slots are falsy, including the blocker case)

Evaluation order

Slots are tested in the order A → B → C → D → E. Slots whose source_X is not connected (C/D/E only) are skipped. The first slot whose condition evaluates truthy wins, and its source_X value is forwarded.

Simple Selector (Switch)

• Category: Lenient Switch
• Display name: Simple Selector (Switch)
• Class: SimpleSelectorSwitch

A no-condition switch: instead of evaluating truthiness, you explicitly pick which source to forward from a dropdown. Each slot also carries a free-form label (a memo), and the chosen slot's label is re-emitted as a second output — handy for things like building a filename from the active choice.

Inputs

Input	Required	Purpose
select	yes	Dropdown none / A / B / C / D / E — which source to forward. none forwards nothing
label_a … label_e	yes	Single-line per-slot memo (e.g. SDXL base). Not used for any flow decision; only the selected slot's label is re-emitted
block_on_none_selected	yes	When select is none, emit an ExecutionBlocker (on both outputs) to skip downstream nodes instead of passing None
bypass_unselected	yes	When ON, only the selected slot's source_X is evaluated; the upstream chains feeding the other sources (or all of them, when select is none) don't run (lazy evaluation, not an rgthree-style mode change)
source_a … source_e	no	Pass-through sources (any type). Wire only the slots you use

Outputs

Output	Type	Meaning
output	any	The source_X of the selected slot. None if select is none (or ExecutionBlocker if block_on_none_selected is ON), or if the selected slot's source is unconnected
label	STRING	The selected slot's label. Empty when select is none

The selector is ComfyUI's stock dropdown — it gives "exactly one, or none" semantics natively with no extra UI. Selecting a slot whose source_X is unconnected returns None (it does not block); only select = none triggers the blocker.

Simple Selector (Switch) Advanced

• Category: Lenient Switch
• Display name: Simple Selector (Switch) Advanced
• Class: SimpleSelectorSwitchAdvanced

Everything Simple Selector (Switch) does, but with a different frontend and an extra bypass_unselected_groups toggle that bypasses whole canvas groups in the rgthree FastGroupsBypasser style.

Exclusive checkbox selector

Instead of the stock dropdown, this node shows an exclusive checkbox list (radio-style) — one row per slot plus a none row, exactly one ticked at a time:

[ ] A  base prompt
[■] B  detail prompt
[ ] C  (unnamed — double-click)
[ ] D  (unnamed — double-click)
[ ] E  (unnamed — double-click)
[ ] none

• Click a row to select that slot (or none). Flow behavior is identical to the plain node.
• Double-click a slot row to edit that slot's label in an inline dialog. (none has no label.)

The selector is a single custom widget: the choice and all five labels are stored together as the widget's value (a small JSON blob) and forwarded to the node — there is no separate dropdown or label fields. The selected slot's label is still re-emitted on the label output.

Group bypass

When bypass_unselected_groups is ON, the canvas group whose name matches each slot's label is:

• set to ALWAYS for the selected slot, and
• set to BYPASS (mode 4 — the greyed-out rgthree look) for every unselected slot.

With none selected, every referenced group is bypassed. When the toggle is OFF, the referenced groups are restored to ALWAYS.

So each slot's label does double duty: it's the per-slot memo / re-emitted label output, and it names the group that slot turns on or off. Name your canvas groups to match the labels (e.g. a group titled SDXL for the slot whose label is SDXL).

Notes:

• This is a pure frontend mode change (it edits other nodes' mode, exactly like rgthree). The plain Simple Selector (Switch) node ships no JS and is unchanged — use it if you don't want any frontend behavior.
• It is orthogonal to bypass_unselected (the lazy-eval toggle). You can run either, both, or neither: lazy-eval controls which source this node evaluates; group bypass controls which canvas groups are mode-4 bypassed.
• Group membership is spatial (a node belongs to a group if it sits inside the group's box), so the toggle re-applies on selection / label changes and on workflow load. After restructuring groups, re-click a row to re-apply.

Known limitation: properties panel

In Nodes 2.0 (Vue rendering), selecting the node opens the right-hand properties panel, which draws the selector a second time. ComfyUI repaints only one of the two copies when you change the selection, so with the panel open the node-body checkboxes can momentarily show a stale choice until they next repaint (click, move, or reload). The selection itself is always correct — only the node-body redraw lags. Close the panel (deselect the node) for the normal, fully-synced view.

Installation

Clone into your ComfyUI custom_nodes directory:

cd ComfyUI/custom_nodes
git clone https://github.com/id-fa/ComfyUI-Lenient-Switch lenient-switch

Restart ComfyUI. No additional dependencies required.

License

MIT