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triplate

Loops & conditionals

{% for %}

{% for c in classes join "UNION" %}
  { ?s a ${c} }
{% endfor %}

{% for <item> in <source> [join "<text>" [explicit]] %} … {% endfor %}.

  • <source> is a declared array parameter, or a path into a loop variable (g.members) for nested loops. Cardinality lives in the header.
  • Join is emitted between iterations only, with boundary whitespace merged. Padded by default (join "UNION" → … } UNION { …); explicit is verbatim (join ", " explicit → "a", "b").
  • A directive alone on its line is removed (block trimming); an inline tag renders in place: VALUES { {% for c in classes %}${c} {% endfor %} }.

{% if %}

{% if nameFilter %}
  FILTER(CONTAINS(?name, ${nameFilter}))
{% endif %}
{% if limit %}LIMIT ${limit}{% else %}LIMIT 100{% endif %}

Conditions are type-directed: a bool tests its value; anything optional tests presence; an array tests non-empty; a required scalar is a compile error (always true). not negates; there are no comparison operators. {% if %} is what makes optional parameters consumable.