72 lines
1.2 KiB
Plaintext
72 lines
1.2 KiB
Plaintext
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Programs
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pattern { action }
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function name (parameter-list) { statement }
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Patterns
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BEGIN
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END
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expresion
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/regular expression/
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pattern && pattern
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pattern || pattern
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!pattern
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(pattern)
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pattern, pattern -> range pattern
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Actions
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break
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continue
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delete array-element
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do statement while (expression)
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exit [expression]
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expression
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if (expression) statement [else statement]
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input-output statement
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for (expression; expression; expression) statement
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for (variable in array) statement
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next
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return [expression]
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while (expression) statement
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{ statements }
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Variables
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global variables (enabled when awk->opt & XP_AWK_OPT_VARDCL)
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global x;
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global x, y;
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local variables (enabled when awk->opt & XP_AWK_OPT_VARDCL)
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local x;
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local x, y;
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function arguments (enabled always)
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function funca (x, y)
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local variables in function declaration (enabled when awk->opt & XP_AWK_OPT_FUNCLOCAL)
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function funca (x, y, v1, v2)
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variables without any declarations (enabled when awk->opt & XP_AWK_OPT_NAMEDVAR)
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x = 10; // x is put into the global hash table.
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Optimization
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constant folding
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2 * 10 => 20
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loop
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remove while (0) { ... }
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if
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remove if (0) {}
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use else_part only
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