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Merging Data

The problem​

You have a template and a JSON data file (or a JavaScript object). You need to merge them into a finished document and render the result.

The solution​

CLI merge​

# Merge and output JSON AST
intenttext template.it --data data.json

# Merge and render HTML
intenttext template.it --data data.json --html

# Merge, render with theme
intenttext template.it --data data.json --html --theme corporate

# Merge to print HTML
intenttext template.it --data data.json --print --theme legal

# Merge to PDF
intenttext template.it --data data.json --pdf --theme corporate

JavaScript merge​

import { parseIntentText, mergeData, render, renderPrint } from "intenttext";

// Two-step merge
const doc = parseIntentText(templateSource);
const merged = mergeData(doc, data);

// Or one-step
import { parseAndMerge } from "intenttext";
const merged = parseAndMerge(templateSource, data);

// Render
const html = render(merged);
const printHtml = renderPrint(merged, { theme: "corporate" });

How merge works​

  1. each: table rows are expanded first (one row per array element)
  2. All {{variable}} occurrences are resolved — in content, properties, table cells, and inline nodes
  3. title: and summary: metadata are also resolved
  4. Missing variables leave {{variable}} visible and add unresolved: 1 to the block

mergeData is a pure function — it never mutates the input document.

Nested data​

Use dot notation for nested objects:

{
  "company": {
    "name": "Acme Corp",
    "address": {
      "city": "San Francisco",
      "state": "CA"
    }
  }
}
text: {{company.name}} is headquartered in {{company.address.city}}, {{company.address.state}}.

Array index access​

Access specific array elements by index:

{
  "contacts": [
    { "name": "Sarah Chen", "role": "CEO" },
    { "name": "James Miller", "role": "CFO" }
  ]
}
contact: {{contacts.0.name}} | role: {{contacts.0.role}}
contact: {{contacts.1.name}} | role: {{contacts.1.role}}

System variables​

These variables are auto-populated without data:

VariableValue
{{date}}Current date (ISO format)
{{year}}Current year
{{timestamp}}Current ISO timestamp
{{agent}}From doc.metadata.agent
{{page}}Page number (left for print renderer)
{{pages}}Total pages (left for print renderer)

Variables in properties​

Variables work everywhere — not just in content:

contact: {{client_name}} | role: {{client_role}} | email: {{client_email}}
deadline: {{milestone_name}} | due: {{milestone_date}} | status: {{milestone_status}}
metric: {{kpi_name}} | value: {{kpi_value}} | target: {{kpi_target}} | unit: {{kpi_unit}}

Handling missing data​

When a variable has no matching value, the block gets unresolved: 1:

const merged = mergeData(doc, { name: "Acme" });

// Blocks with missing variables have:
// { unresolved: 1, content: "Contact {{missing_email}} for details" }

Find unresolved blocks:

intenttext template.it --data partial.json --query "unresolved=1"

This is intentional design. A template with partial data should still produce a useful document — not crash.

Security​

The merge engine enforces limits:

  • Path depth: maximum 20 levels of nesting
  • Path length: maximum 200 characters
  • Blocked keys: __proto__, constructor, prototype

These limits prevent prototype pollution and excessive resource consumption.

Next steps​