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Binary Format: Strings

Strings are stored in a centralized pool to eliminate redundancy and alignment padding overhead. They are referenced by StringId throughout the file.

Primitives

StringId (u16): Zero-based index into the String Table.

Reserved StringId(0)

StringId(0) is reserved and contains an easter egg: "Beauty will save the world" (Dostoevsky, The Idiot).

This reservation has a practical purpose: since Match instructions use 0 to indicate "no constraint" (wildcard), StringId(0) can never appear in unlinked bytecode instructions. User strings start at index 1.

1. String Blob

Contains the raw UTF-8 bytes for all strings concatenated together.

  • Section Offset: Computed (first section after header, at offset 64)
  • Size: header.str_blob_size
  • Content: Raw bytes. Strings are not null-terminated.
  • Padding: The section is padded to a 64-byte boundary at the end.

2. String Table

Lookup table mapping StringId to byte offsets within the String Blob.

  • Section Offset: Computed (follows RegexBlob, 64-byte aligned)
  • Record Size: 4 bytes (u32).
  • Capacity: header.str_table_count + 1 entries.
    • The table contains one extra entry at the end representing the total size of the unpadded blob.

Lookup Logic

To retrieve string i (where 0 <= i < header.str_table_count):

  1. Read start = table[i]
  2. Read end = table[i+1]
  3. Length = end - start
  4. Data = blob[start..end]
// Logical layout (not a single struct)
struct StringTable {
    offsets: [u32; header.str_table_count + 1],
}

Limit: Maximum str_table_count is 65,534 (0xFFFE). The table requires count + 1 entries for length calculation, and the extra entry must fit in addressable space.

Example

Stored strings: "id", "foo"

String Blob:

0x00: 'i', 'd', 'f', 'o', 'o'
... padding to 64 bytes ...

String Table (str_table_count = 2):

0x00: 0  (Offset of "id")
0x04: 2  (Offset of "foo")
0x08: 5  (End of blob, used to calculate length of "foo")