{
    "mode": "perldoc",
    "parameter": "integer",
    "section": "",
    "url": "https://www.chedong.com/phpMan.php/perldoc/integer/json",
    "generated": "2026-06-13T10:49:05Z",
    "synopsis": "use integer;\n$x = 10/3;\n# $x is now 3, not 3.33333333333333333",
    "sections": {
        "NAME": {
            "content": "integer - Perl pragma to use integer arithmetic instead of floating point\n",
            "subsections": []
        },
        "SYNOPSIS": {
            "content": "use integer;\n$x = 10/3;\n# $x is now 3, not 3.33333333333333333\n",
            "subsections": []
        },
        "DESCRIPTION": {
            "content": "This tells the compiler to use integer operations from here to the end of the enclosing BLOCK.\nOn many machines, this doesn't matter a great deal for most computations, but on those without\nfloating point hardware, it can make a big difference in performance.\n\nNote that this only affects how most of the arithmetic and relational operators handle their\noperands and results, and not how all numbers everywhere are treated. Specifically, \"use\ninteger;\" has the effect that before computing the results of the arithmetic operators (+, -, *,\n/, %, +=, -=, *=, /=, %=, and unary minus), the comparison operators (<, <=, >, >=, ==, !=,\n<=>), and the bitwise operators (|, &, ^, <<, >>, |=, &=, ^=, <<=, >>=), the operands have their\nfractional portions truncated (or floored), and the result will have its fractional portion\ntruncated as well. In addition, the range of operands and results is restricted to that of\nfamiliar two's complement integers, i.e., -(231) .. (231-1) on 32-bit architectures, and\n-(263) .. (263-1) on 64-bit architectures. For example, this code\n\nuse integer;\n$x = 5.8;\n$y = 2.5;\n$z = 2.7;\n$a = 231 - 1;  # Largest positive integer on 32-bit machines\n$, = \", \";\nprint $x, -$x, $x+$y, $x-$y, $x/$y, $x*$y, $y==$z, $a, $a+1;\n\nwill print: 5.8, -5, 7, 3, 2, 10, 1, 2147483647, -2147483648\n\nNote that $x is still printed as having its true non-integer value of 5.8 since it wasn't\noperated on. And note too the wrap-around from the largest positive integer to the largest\nnegative one. Also, arguments passed to functions and the values returned by them are not\naffected by \"use integer;\". E.g.,\n\nsrand(1.5);\n$, = \", \";\nprint sin(.5), cos(.5), atan2(1,2), sqrt(2), rand(10);\n\nwill give the same result with or without \"use integer;\" The power operator \"\" is also not\naffected, so that 2  .5 is always the square root of 2. Now, it so happens that the pre- and\npost- increment and decrement operators, ++ and --, are not affected by \"use integer;\" either.\nSome may rightly consider this to be a bug -- but at least it's a long-standing one.\n\nFinally, \"use integer;\" also has an additional affect on the bitwise operators. Normally, the\noperands and results are treated as unsigned integers, but with \"use integer;\" the operands and\nresults are signed. This means, among other things, that ~0 is -1, and -2 & -5 is -6.\n\nInternally, native integer arithmetic (as provided by your C compiler) is used. This means that\nPerl's own semantics for arithmetic operations may not be preserved. One common source of\ntrouble is the modulus of negative numbers, which Perl does one way, but your hardware may do\nanother.\n\n% perl -le 'print (4 % -3)'\n-2\n% perl -Minteger -le 'print (4 % -3)'\n1\n\nSee \"Pragmatic Modules\" in perlmodlib, \"Integer Arithmetic\" in perlop\n",
            "subsections": []
        }
    },
    "summary": "integer - Perl pragma to use integer arithmetic instead of floating point",
    "flags": [],
    "examples": [],
    "see_also": []
}