Complete Syntax Reference
IDEAL Survey maintains ODK compatibility while offering cleaner, more intuitive syntax.
Green rows indicate IDEAL-exclusive enhancements not available in standard ODK.
| Feature | ODK Syntax | IDEAL Syntax |
|---|---|---|
| Basic ref | ${question_name} | {question_name} |
| Cross-survey | pulldata('survey', 'field', 'id', 'value') | {s1:question_name} |
| Repeat instance | indexed-repeat(${name}, ${family}, position(..)) | {family[0].name} |
| Last instance | indexed-repeat(${name}, ${family}, count(${family})) | {family[-1].name} |
| Current instance | ${name} | {.name} |
| Count | count(${family}) | {family.count} |
| Sum | sum(${items}/price) | {items[*].price.sum} |
| Average | sum(${items}/price) div count(${items}) | {items[*].price.avg} |
| Min/Max | min(${items}/price) | {items[*].price.min} |
| Arithmetic | ${price} * ${quantity} | {price} * {quantity} |
| Conditional | if(${age} >= 18, 'Adult', 'Minor') | {age} >= 18 ? 'Adult' : 'Minor' |
| Complex calc | (${baseline} - ${followup}) div ${baseline} * 100 | ({baseline} - {followup}) / {baseline} * 100 |
| Table cell | Not supported | {table_name[0].column_name} |
| Table column | Not supported | {table_name[*].column_name} |
| Table last row | Not supported | {table_name[-1].column_name} |
| Table col agg | Not supported | {table_name[*].column_name.avg} |
| Table row count | Not supported | {table_name.rows} |
| Cross-survey table | Not supported | {survey_name:table_name[*].column_name.sum} |
| Nested repeat ref | Not supported | {outer[*].inner[*].field} |
| Nested repeat agg | Not supported | {outer[*].inner[*].field.sum} |
| Cross-survey nested | Not supported | {s12:outer[*].inner[*].field.sum} |
| Nested multi-select | Not supported | {outer[0].inner[0].field[1]} |
| Dynamic options | Not supported | {question_name} as an option value |
| Dynamic table rows | Not supported | {question_name} as a row label |
| Dynamic table cols | Not supported | {question_name} as a column label |
| Bulk columns | Not supported | Column: A, B, C (comma-separated in editor) |
| Instance title | Not supported | {table[$i].column} in group label |
| Sibling ref | Not supported | {.sub_question_name} |
| Table default val | Not supported | {calc_field} as number column default |
| All instances | Manual iteration | {family[*].name} |
| Filter and agg | Complex workarounds | {family[age>18].income.avg} |
| Custom sep | Not supported | {family[*].name|join:"; "} |
| Text format | Limited | {name|uppercase} |
| Number format | Not supported | {score|number:2} |
| Truncate | Not supported | {text|truncate:50} |
| Fallback | Not supported | {q1 ?? 'N/A'} |
| Chained ops | Not supported | {score|number:2 ?? '0.00'} |
| Rich text | Limited HTML | **bold** *italic* __underline__ [color:blue]text[/color] |
All Supported Functions
Note: Functions like round(), abs(), max(), min() and arithmetic operators are only available in Calculate question types. In regular question text, you can use formatters (|uppercase, |number:2) and aggregations (.sum, .avg) but not arithmetic operations.
| Category | Function | Description | Example |
|---|---|---|---|
| Aggregate | .sum | Add all values | {items[*].price.sum} |
.avg | Calculate average | {scores[*].value.avg} | |
.min | Find minimum | {prices[*].amount.min} | |
.max | Find maximum | {scores[*].value.max} | |
.count | Count instances | {family.count} | |
| Text Format | |uppercase | Convert to uppercase | {name|uppercase} |
|lowercase | Convert to lowercase | {name|lowercase} | |
|capitalize | Capitalize first letter | {name|capitalize} | |
|trim | Remove leading/trailing spaces | {text|trim} | |
|truncate:N | Limit to N characters with ... | {text|truncate:50} | |
|join:"sep" | Join array with custom separator | {names|join:"; "} | |
| Number Format | |number:N | Format with N decimal places | {score|number:2} |
round() | Round to nearest integer | round({value}) | |
abs() | Absolute value | abs({diff}) | |
max(a,b) | Maximum of two values | max({a}, {b}) | |
min(a,b) | Minimum of two values | min({a}, {b}) |
Arithmetic Operations
Use standard arithmetic operators in Calculate question types to perform mathematical operations.
Addition: {a} + {b}
Subtraction: {total} - {discount}
Multiplication: {price} * {quantity}
Division: {total} / {count}
Comparison Operators
Use comparison operators in constraints and conditional logic to evaluate conditions.
Equals: === (e.g., {status} === "active")
Not equals: !== (e.g., {type} !== "draft")
Greater than: > (e.g., {age} > 18)
Greater or equal: >= (e.g., {score} >= 90)
Less than: < (e.g., {price} < 100)
Less or equal: <= (e.g., {quantity} <= 10)
Validation Constraints
Add constraints to questions to enforce data quality. The constraint expression must evaluate to true for the answer to be accepted. Use . to refer to the current question's value.
Min value: . >= 0
Range: . >= 1 && . <= 10
Not empty: . !== ''
Min length: .length >= 3
Regex pattern: regex(., '^[A-Z]+$')
Reference other question: . > {minAge}
Check multi-select includes: {choices}.includes('Yes')
Conditional Constraints
Use the pattern !condition || validation to only enforce a rule when a condition is met. The constraint passes if the condition is false OR the validation is true.
Require >= 3 only if "Yes" selected: !{multiQ}.includes('Yes') || . >= 3
Require non-empty only if another field is filled: !{otherQ} || . !== ''
Max 100 only when type is "percentage": {type} !== 'percentage' || . <= 100
Conditional Logic
Use ternary operators for conditional calculations in Calculate question types.
Basic ternary: {age} >= 18 ? 'Adult' : 'Minor'
With calculation: {age} >= 65 ? {price} * 0.8 : {price}
Nested conditions: {score} < 60 ? 'F' : {score} < 70 ? 'D' : 'C+'
Filtering Repeat Groups
Filter repeat group instances based on conditions before aggregating or displaying. This is an IDEAL-exclusive feature.
Filter by age: {family[age>=18].name} - Shows names of adults only
Filter by score: {students[grade>=90].name} - Shows high performers
Filter by category: {items[category==="food"].price.sum} - Sum food prices
Filter and aggregate: {family[age>18].income.avg} - Average adult income
Count filtered: {students[grade>=90].name.count} - Count A students
Practical Examples
| Use Case | Syntax |
|---|---|
| Display previous answer | You entered: {name} |
| Calculate total price | {price} * {quantity} |
| Sum all prices | {items[*].price.sum} |
| Average income for adults | {family[age>18].income.avg} |
| Format score with fallback | {score|number:2 ?? '0.00'} |
| Reference previous survey | Baseline score: {baseline:total_score} |
| List names with custom separator | {family[*].name|join:"; "} |
| Senior discount calculation | {age} >= 65 ? {price} * 0.8 : {price} |
| Dynamic options from previous answer | {crops} as a choice option → expands to each selected crop |
| Dynamic table columns from answer | {crops} as column label → one column per crop |
| Reference sibling in repeat group | {.price} * {.quantity} (within same instance) |
| Table number default from calculate | {baseline_value} as default value in number column |
| Complex calculation example | {weight} / (({height} / 100) * ({height} / 100)) | number:1 |
| Nested repeat group values | {households[*].members[*].name} |
| Nested repeat group sum | {households[*].members[*].income.sum} |
| Cross-survey nested repeat | {s12:outer[*].inner[*].field.avg} |