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Compare two version strings (string.compare_version)

Declaration​

cmp = string.compare_version(ver_a, ver_b)

Parameters​

  • ver_a, ver_b
    string. Versions to compare.

Returns​

  • cmp
    integer. 1 if ver_a > ver_b, -1 if ver_a < ver_b, 0 if equal.

Description​

Compare two version strings using rules:

  • Split by '.' or '-' or spaces as numeric segments (multiple separators collapse as one)
  • Higher weight to left-most segments
  • Stop at first illegal character
  • Pad missing segments with '0'
  • Empty or illegal strings are treated as '0'
  • Examples: '1.1' == '1.1.0' == '1-1'; '1.0' == '1 0'; '1.0' > '0.99999'
  • Usable in XUI

Examples​

-- Equivalence examples
assert(string.compare_version("", "") == 0)
assert(string.compare_version("1", "") == 1)
assert(string.compare_version("", "1") == -1)
assert(string.compare_version("1", "1") == 0)
assert(string.compare_version("1.0", "1") == 0)
assert(string.compare_version("1", "1.0") == 0)
assert(string.compare_version("1.", "1") == 0)
assert(string.compare_version("1", "1.") == 0)
assert(string.compare_version("1.", "1.0") == 0)
assert(string.compare_version("1.0", "1.") == 0)
assert(string.compare_version("1.0", "1.0") == 0)
assert(string.compare_version("1.0.0", "1.0.0") == 0)

-- Greater / less examples
assert(string.compare_version("1.1", "1.0") == 1)
assert(string.compare_version("1.0", "1.1") == -1)
assert(string.compare_version("1.1", "1.10") == -1)
assert(string.compare_version("1.2", "1.11") == -1)
assert(string.compare_version("1.1", "1.1.1") == -1)
assert(string.compare_version("1.2", "1.1.1") == 1)
assert(string.compare_version("1.0", "0.99999") == 1)
assert(string.compare_version("1.10.1", "1.10") == 1)
assert(string.compare_version("1.2-4", "1.2-3") == 1)
assert(string.compare_version("1.2-3", "1.2.3") == 0)
assert(string.compare_version("1.2-4", "1.2.3.0") == 1)
assert(string.compare_version("1.2-4", "1.2.3.10") == 1)
assert(string.compare_version("1.2-4", "1.2.30.10") == -1)
assert(string.compare_version("1.2-3", "1.2.4") == -1)
assert(string.compare_version("2.2", "1.2") == 1)
assert(string.compare_version("2.2", "10.2") == -1)
assert(string.compare_version("2..2", "2.2") == 0)
assert(string.compare_version("2.2.x.3", "2.2") == 0)
assert(string.compare_version("x", "") == 0)