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Form Field Conditions

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    Show/hide conditions on form fields, including the shared {{ condition }} shape and each typed condition object.

    Each form field has exactly one condition. That value is polymorphic: Liquid exposes it as {{ condition }}, but at runtime it is one of the typed condition objects on this page. Use object_type or type to tell which implementing type you have.

    To combine tests, nest them in an and_condition or or_condition. Those groups hold a list of condition objects, and groups may nest.

    {{ condition }} documents only the shared properties. Typed objects add the rest (field_id, value, invert, and so on). These are form-field show/hide conditions, not Liquid {% if %} operators — those stay on Conditions Overview.

    {{ condition }}

    {{ condition }} is the shared shape for a form field's show/hide rule. It is not a separate runtime type: each field has exactly one condition, and that value is one of the typed condition objects (eq_condition, and_condition, and the rest). Use object_type or type to tell which implementing type you have.

    Properties
    Name Type Description
    is_valid boolean Will be true when the condition exists and is valid
    object_type string The object_type of the implementing condition (for example eq_condition or and_condition)
    type string The type of condition. Each type corresponds to a different condition object which has its own additional properties
    output string {JSON object}

    Typed condition objects add further properties that are not listed here (for example field_id, value, invert, or a nested conditions list). See each type on this page. Multiple tests are grouped with and_condition or or_condition; those groups may nest.

    Example Tell which typed condition a form field has{{ condition }} is polymorphic: check object_type to know which typed condition object you actually have before reading its extra properties.
    Liquid
    {%- if form_field.condition.object_type == "eq_condition" -%}
	Visible when {{ form_field.condition.field_id }} equals "{{ form_field.condition.value }}"
{%- elsif form_field.condition.object_type == "and_condition" -%}
	Visible when all {{ form_field.condition.conditions | size }} conditions are true
{%- else -%}
	Visible based on a {{ form_field.condition.type }} condition
{%- endif -%}

    form_field.condition is always {{ condition }}'s shared shape at compile time, but only object_type tells you which typed condition it is at runtime. eq_condition and and_condition each add their own properties (field_id/value, and a nested conditions list) that only exist once you know the type.

    {{ and_condition }}

    A grouped form-field condition that is true when every nested condition is true.

    Properties
    Name Type Description
    is_valid boolean Will be true when this group contains one or more nested conditions
    object_type string Will always be "and_condition"
    type string Will always be "and"
    invert boolean When true, the grouped result is reversed
    conditions list The list of nested condition objects that must all be true. Each item is one of the typed {{ condition }} objects. Groups may nest and_condition and or_condition
    output string {JSON object}
    Example Tell which typed condition a form field has{{ condition }} is polymorphic: check object_type to know which typed condition object you actually have before reading its extra properties.
    Liquid
    {%- if form_field.condition.object_type == "eq_condition" -%}
	Visible when {{ form_field.condition.field_id }} equals "{{ form_field.condition.value }}"
{%- elsif form_field.condition.object_type == "and_condition" -%}
	Visible when all {{ form_field.condition.conditions | size }} conditions are true
{%- else -%}
	Visible based on a {{ form_field.condition.type }} condition
{%- endif -%}

    form_field.condition is always {{ condition }}'s shared shape at compile time, but only object_type tells you which typed condition it is at runtime. eq_condition and and_condition each add their own properties (field_id/value, and a nested conditions list) that only exist once you know the type.

    {{ contains_condition }}

    A form-field condition that is true when a list field contains a given value.

    Properties
    Name Type Description
    is_valid boolean Will be true when field_id and value are set
    object_type string Will always be "contains_condition"
    type string Will always be "contains"
    invert boolean When true, the condition is true when the field does not contain the value
    field_id string The field_id of the list field to test
    value string The value to look for in the target field
    output string {JSON object}
    Example Show text when a contains_condition matchescontains_condition tests whether a list field includes a given value; field_id names the list field, value is what to look for.
    Liquid
    {%- if form_field.condition.object_type == "contains_condition" -%}
	Visible when {{ form_field.condition.field_id }} includes "{{ form_field.condition.value }}"
{%- endif -%}

    contains_condition is the typed condition for a list-field show/hide rule. field_id names the field being tested and value is the item it must contain; invert (unused here) flips the test to "does not contain".

    {{ eq_condition }}

    A form-field condition that is true when another field's value equals a given value.

    Properties
    Name Type Description
    is_valid boolean Will be true when field_id and value are set
    object_type string Will always be "eq_condition"
    type string Will always be "eq"
    invert boolean When true, the condition is true when the values are not equal
    field_id string The field_id of the field to compare
    value string The value that the target field must equal
    output string {JSON object}
    Example Tell which typed condition a form field has{{ condition }} is polymorphic: check object_type to know which typed condition object you actually have before reading its extra properties.
    Liquid
    {%- if form_field.condition.object_type == "eq_condition" -%}
	Visible when {{ form_field.condition.field_id }} equals "{{ form_field.condition.value }}"
{%- elsif form_field.condition.object_type == "and_condition" -%}
	Visible when all {{ form_field.condition.conditions | size }} conditions are true
{%- else -%}
	Visible based on a {{ form_field.condition.type }} condition
{%- endif -%}

    form_field.condition is always {{ condition }}'s shared shape at compile time, but only object_type tells you which typed condition it is at runtime. eq_condition and and_condition each add their own properties (field_id/value, and a nested conditions list) that only exist once you know the type.

    {{ exists_condition }}

    A form-field condition that is true when another field has a value.

    Properties
    Name Type Description
    is_valid boolean Will be true when field_id is set
    object_type string Will always be "exists_condition"
    type string Will always be "exists"
    invert boolean When true, the condition is true when the target field does not have a value
    field_id string The field_id of the field whose presence is tested
    output string {JSON object}
    Example Show text when an exists_condition matchesexists_condition is true once another field has any value at all — it takes only field_id, no value to compare against.
    Liquid
    {%- if form_field.condition.object_type == "exists_condition" -%}
	Visible once {{ form_field.condition.field_id }} has a value
{%- endif -%}

    Unlike eq_condition or gt_condition, exists_condition has no value property to read — presence alone is the whole test. field_id is the only thing that identifies what is being checked.

    {{ gt_condition }}

    A form-field condition that is true when another field's value is greater than a given value.

    Properties
    Name Type Description
    is_valid boolean Will be true when field_id and value are set
    object_type string Will always be "gt_condition"
    type string Will always be "gt"
    field_id string The field_id of the field to compare
    value string The value that the target field must be greater than
    output string {JSON object}
    Example Tell a strict threshold from an inclusive onegt_condition and gte_condition share field_id and value, but only gte_condition includes the boundary value itself — check object_type to know which you have.
    Liquid
    {%- if form_field.condition.object_type == "gt_condition" -%}
	Visible when {{ form_field.condition.field_id }} is greater than {{ form_field.condition.value }}
{%- elsif form_field.condition.object_type == "gte_condition" -%}
	Visible when {{ form_field.condition.field_id }} is {{ form_field.condition.value }} or greater
{%- endif -%}

    Both types compare a field's value against value using the same two properties, so the only way to tell a strict greater-than from an inclusive one is object_type — the wording each produces differs by exactly whether the boundary value itself counts.

    {{ gte_condition }}

    A form-field condition that is true when another field's value is greater than or equal to a given value.

    Properties
    Name Type Description
    is_valid boolean Will be true when field_id and value are set
    object_type string Will always be "gte_condition"
    type string Will always be "gte"
    field_id string The field_id of the field to compare
    value string The value that the target field must be greater than or equal to
    output string {JSON object}
    Example Tell a strict threshold from an inclusive onegt_condition and gte_condition share field_id and value, but only gte_condition includes the boundary value itself — check object_type to know which you have.
    Liquid
    {%- if form_field.condition.object_type == "gt_condition" -%}
	Visible when {{ form_field.condition.field_id }} is greater than {{ form_field.condition.value }}
{%- elsif form_field.condition.object_type == "gte_condition" -%}
	Visible when {{ form_field.condition.field_id }} is {{ form_field.condition.value }} or greater
{%- endif -%}

    Both types compare a field's value against value using the same two properties, so the only way to tell a strict greater-than from an inclusive one is object_type — the wording each produces differs by exactly whether the boundary value itself counts.

    {{ in_condition }}

    A form-field condition that is true when another field's value is one of a delimited list of values.

    Properties
    Name Type Description
    is_valid boolean Will be true when field_id, value, and delimiter are set
    object_type string Will always be "in_condition"
    type string Will always be "in"
    invert boolean When true, the condition is true when the field's value is not in the list
    field_id string The field_id of the field to compare
    value string The delimited list of values to match against
    delimiter string The string that separates values in the value list
    values list The parsed list of values to match against
    output string {JSON object}
    Example Show text when an in_condition matchesin_condition tests a field's value against a delimited list of candidates — value holds the raw delimited string, delimiter the separator.
    Liquid
    {%- if form_field.condition.object_type == "in_condition" -%}
	Visible when {{ form_field.condition.field_id }} is one of "{{ form_field.condition.value }}" ({{ form_field.condition.delimiter }}-separated)
{%- endif -%}

    in_condition stores its candidate list as one delimited string (value) plus the delimiter used to split it, rather than as a pre-split list — read both together to describe the rule accurately.

    {{ lt_condition }}

    A form-field condition that is true when another field's value is less than a given value.

    Properties
    Name Type Description
    is_valid boolean Will be true when field_id and value are set
    object_type string Will always be "lt_condition"
    type string Will always be "lt"
    field_id string The field_id of the field to compare
    value string The value that the target field must be less than
    output string {JSON object}
    Example Tell a strict threshold from an inclusive onelt_condition and lte_condition share field_id and value, but only lte_condition includes the boundary value itself — check object_type to know which you have.
    Liquid
    {%- if form_field.condition.object_type == "lt_condition" -%}
	Visible when {{ form_field.condition.field_id }} is less than {{ form_field.condition.value }}
{%- elsif form_field.condition.object_type == "lte_condition" -%}
	Visible when {{ form_field.condition.field_id }} is {{ form_field.condition.value }} or less
{%- endif -%}

    Both types compare a field's value against value using the same two properties, so the only way to tell a strict less-than from an inclusive one is object_type — mirrors gt_condition/gte_condition on the other side of the comparison.

    {{ lte_condition }}

    A form-field condition that is true when another field's value is less than or equal to a given value.

    Properties
    Name Type Description
    is_valid boolean Will be true when field_id and value are set
    object_type string Will always be "lte_condition"
    type string Will always be "lte"
    field_id string The field_id of the field to compare
    value string The value that the target field must be less than or equal to
    output string {JSON object}
    Example Tell a strict threshold from an inclusive onelt_condition and lte_condition share field_id and value, but only lte_condition includes the boundary value itself — check object_type to know which you have.
    Liquid
    {%- if form_field.condition.object_type == "lt_condition" -%}
	Visible when {{ form_field.condition.field_id }} is less than {{ form_field.condition.value }}
{%- elsif form_field.condition.object_type == "lte_condition" -%}
	Visible when {{ form_field.condition.field_id }} is {{ form_field.condition.value }} or less
{%- endif -%}

    Both types compare a field's value against value using the same two properties, so the only way to tell a strict less-than from an inclusive one is object_type — mirrors gt_condition/gte_condition on the other side of the comparison.

    {{ maxitems_condition }}

    A form-field condition that is true when a list field has at most a given number of selected items.

    Properties
    Name Type Description
    is_valid boolean Will be true when field_id is set and value is greater than 0
    object_type string Will always be "maxitems_condition"
    type string Will always be "maxitems"
    field_id string The field_id of the list field to test
    value integer The maximum number of selected items
    output string {JSON object}
    Example Read a selection-count condition's limitmaxitems_condition and minitems_condition both count selections on a list field; value holds the limit, but which limit it is again depends on object_type.
    Liquid
    {%- if form_field.condition.object_type == "maxitems_condition" -%}
	Visible while {{ form_field.condition.field_id }} has {{ form_field.condition.value }} or fewer selections
{%- elsif form_field.condition.object_type == "minitems_condition" -%}
	Visible once {{ form_field.condition.field_id }} has {{ form_field.condition.value }} or more selections
{%- endif -%}

    Both types are only valid once field_id is set and value is greater than 0 — a value of 0 (or an unset field_id) means the condition itself is not yet configured, not that the limit is zero items.

    {{ mimic_condition }}

    Reuses another field's show/hide condition so you do not have to redefine the same rule on every field.

    Properties
    Name Type Description
    is_valid boolean Will be true when field_id is set
    object_type string Will always be "mimic_condition"
    type string Will always be "mimic"
    invert boolean When true, the mimicked result is reversed
    field_id string The field_id of the field whose condition should be reused
    output string {JSON object}

    mimic_condition lets you define a condition on a single field and apply that same rule to other fields without rewriting it. Liquid does not currently link to the referenced field; the template developer must look up that field and apply the result themselves.

    Example Show text when a mimic_condition matchesmimic_condition reuses another field's own condition instead of restating the same rule — field_id names the field whose condition to copy, not a field to compare against.
    Liquid
    {%- if form_field.condition.object_type == "mimic_condition" -%}
	Reuses the show/hide rule from {{ form_field.condition.field_id }}
{%- endif -%}

    mimic_condition is not a comparison: it has no value property, because it does not test a value — it points at another field's condition and copies that field's result, optionally reversed with invert.

    {{ minitems_condition }}

    A form-field condition that is true when a list field has at least a given number of selected items.

    Properties
    Name Type Description
    is_valid boolean Will be true when field_id is set and value is greater than 0
    object_type string Will always be "minitems_condition"
    type string Will always be "minitems"
    field_id string The field_id of the list field to test
    value integer The minimum number of selected items
    output string {JSON object}
    Example Read a selection-count condition's limitmaxitems_condition and minitems_condition both count selections on a list field; value holds the limit, but which limit it is again depends on object_type.
    Liquid
    {%- if form_field.condition.object_type == "maxitems_condition" -%}
	Visible while {{ form_field.condition.field_id }} has {{ form_field.condition.value }} or fewer selections
{%- elsif form_field.condition.object_type == "minitems_condition" -%}
	Visible once {{ form_field.condition.field_id }} has {{ form_field.condition.value }} or more selections
{%- endif -%}

    Both types are only valid once field_id is set and value is greater than 0 — a value of 0 (or an unset field_id) means the condition itself is not yet configured, not that the limit is zero items.

    {{ or_condition }}

    A grouped form-field condition that is true when any nested condition is true.

    Properties
    Name Type Description
    is_valid boolean Will be true when this group contains one or more nested conditions
    object_type string Will always be "or_condition"
    type string Will always be "or"
    invert boolean When true, the grouped result is reversed
    conditions list The list of nested condition objects. The group passes when any item is true. Each item is one of the typed {{ condition }} objects. Groups may nest and_condition and or_condition
    output string {JSON object}
    Example Count how many nested conditions an or_condition groupsor_condition groups nested conditions the same way and_condition does, but passes when any one of them is true instead of requiring all of them.
    Liquid
    {%- if form_field.condition.object_type == "or_condition" -%}
	Visible when any of {{ form_field.condition.conditions | size }} conditions is true
{%- endif -%}

    conditions holds the nested list, exactly as and_condition does — the two group types share that shape and differ only in whether they require all nested conditions or just one. Groups may nest and_condition and or_condition inside each other.