Template literal types were not inheriting validation tags when intersected with tags likeMaxLength andPattern. This caused validation to pass incorrectly when it should fail.

Problem

Consider this type intersection:

typeTaggedTemplate=tags.MaxLength<10>&tags.Pattern<'^[a-zA-Z0-9_]+$'>&                      `prefix${string}postfix`;consttestValue='prefix;"+,df0123456789postfix';// 28 chars, special characters// Before fix: This would pass validation (incorrect)typia.validate<TaggedTemplate>(testValue);// { success: true }// But regular string with same tags would fail correctlytypia.validate<tags.MaxLength<10>&tags.Pattern<'^[a-zA-Z0-9_]+$'>&string>(testValue);// { success: false, errors: [...] }

The issue affected all validation functions:validate,assert,is, and schema generation.

Root Cause

The intersection handler correctly processed validation tags and attached them to template literal metadata. However, the code generator for templates (check_template) was only generating pattern matching code and ignoring thetpl.tags field, unlikecheck_string which processes both type checking and validation tags.

Solution

Modifiedsrc/programmers/internal/check_template.ts to:

1. Add validation tag processing: Createdcheck_template_type_tags function similar tocheck_string_type_tags
2. Generate validation conditions: Process tags withvalidate scripts and transpile them to runtime checks
3. Combine all validations: Return conditions that include template pattern matching AND validation tag checking

Updated call sites inCheckerProgrammer.ts andcheck_dynamic_key.ts to pass the requiredcontext parameter.

After Fix

// Now correctly fails validationtypia.validate<TaggedTemplate>('prefix;"+,df0123456789postfix');// {//   success: false,//   errors: [//     { expected: "string & MaxLength<10>", ... },//     { expected: "string & Pattern<'^[a-zA-Z0-9_]+$'>", ... }//   ]// }// Valid values pass as expectedtypia.validate<TaggedTemplate>('prefix123pos');// { success: true }

The fix ensures template literals validate against:

1. Template structure (must matchprefix*postfix pattern)
2. Length constraints (MaxLength<10>)
3. Pattern constraints (Pattern<'^[a-zA-Z0-9_]+$'>)

Fixes#1635.

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