angular/angular · error · Error

@loading block can only have one "minimum" parameter

Error message

@loading block can only have one "minimum" parameter

What it means

An @loading sub-block of @defer declares the `minimum` parameter more than once. `minimum` controls how long the loading indicator stays visible once shown; the compiler keeps it in a single `minimumTime` field, so when the parameter loop encounters a second /^minimum\s/ match while `minimumTime != null`, it throws.

Source

Thrown at packages/compiler/src/render3/r3_deferred_blocks.ts:226

  for (const param of ast.parameters) {
    if (AFTER_PARAMETER_PATTERN.test(param.expression)) {
      if (afterTime != null) {
        throw new Error(`@loading block can only have one "after" parameter`);
      }

      const parsedTime = parseDeferredTime(
        param.expression.slice(getTriggerParametersStart(param.expression)),
      );

      if (parsedTime === null) {
        throw new Error(`Could not parse time value of parameter "after"`);
      }

      afterTime = parsedTime;
    } else if (MINIMUM_PARAMETER_PATTERN.test(param.expression)) {
      if (minimumTime != null) {
        throw new Error(`@loading block can only have one "minimum" parameter`);
      }

      const parsedTime = parseDeferredTime(
        param.expression.slice(getTriggerParametersStart(param.expression)),
      );

      if (parsedTime === null) {
        throw new Error(`Could not parse time value of parameter "minimum"`);
      }

      minimumTime = parsedTime;
    } else {
      throw new Error(`Unrecognized parameter in @loading block: "${param.expression}"`);
    }
  }

  return new t.DeferredBlockLoading(
    html.visitAll(visitor, ast.children, ast.children),

View on GitHub (pinned to 51cb07e980)

Solutions

1. Delete the duplicate and keep one `minimum` parameter
2. If you intended two timings, use the valid combination `after <time>; minimum <time>`

Example fix

// before
@loading (minimum 1s; minimum 2s) {
  Loading...
}
// after
@loading (minimum 2s) {
  Loading...
}

function validateLoadingParams(params: string[]): string | null {
  const minCount = params.filter((p) => /^minimum\s/.test(p)).length;
  return minCount > 1 ? 'Duplicate "minimum" parameter in @loading' : null;
}

When it happens

Trigger: `@loading (minimum 1s; minimum 2s) {...}` — two parameters matching /^minimum\s/ in the same @loading block (parameters separated by `;`).

Common situations: Duplicating a parameter while copy-pasting timing configuration, or merging templates after a refactor. Developers sometimes add a second `minimum` intending to change the value instead of editing the first one.

Related errors

• @loading block can only have one "after" parameter
• Unrecognized parameter in @loading block: "${param.expressio
• Unrecognized parameter in @placeholder block: "${param.expre
• Could not parse time value of parameter "after"
• @error block cannot have parameters

AI-assisted analysis of angular/angular@51cb07e980 (2026-08-22). Data as JSON: /api/errors/400a30c3d5f8bd9c. Report an issue: GitHub.