# S3729: Array indices should be placed between brackets
id: no-pointer-arithmetic-array-access
name: Array Indices Should Use Bracket Notation
severity: error
category: maintainability
defect_class: correctness
inline_tier: blocking
language: c

message: "use array bracket notation instead of pointer arithmetic for indexing"

description: |
  `*(arr + i)` is equivalent to `arr[i]` but less clear. Bracket notation
  makes the intent obvious and is the idiomatic form in C.

  ✅ FIX: Replace with bracket notation

  ```c
  int val = arr[3];  // GOOD - clear intent
  ```

query: |
  (pointer_expression
    "*"
    (parenthesized_expression
      (binary_expression
        (_) @ARRAY
        "+"
        (_) @INDEX))) @EXPR

metavars:
  - ARRAY
  - INDEX
  - EXPR

tags:
  - maintainability
  - c
  - pitfall
  - readability

examples:
  bad: |
    int val = *(arr + 3);  // BAD - unclear

  good: |
    int val = arr[3];      // GOOD - idiomatic

has_fix: true
fix_action: convert_to_bracket_notation