There is no 'u' flag. Integers are printed unsigned if they have unsigned type.
Similarly, there is no need to specify the size of the operand (int8, int64).
- The width and precision control formatting and are in units of Unicode
- code points. (This differs from C's printf where the units are numbers
+ Width is specified by an optional decimal number immediately following the verb.
+ If absent, the width is whatever is necessary to represent the value.
+ Precision is specified after the (optional) width by a period followed by a
+ decimal number. If no period is present, a default precision is used.
+ A period with no following number specifies a precision of zero.
+ Examples:
+ %f: default width, default precision
+ %9f width 9, default precision
+ %.2f default width, precision 2
+ %9.2f width 9, precision 2
+ %9.f width 9, precision 0
+
+ Width and precision are measured in units of Unicode code points.
+ (This differs from C's printf where the units are numbers
of bytes.) Either or both of the flags may be replaced with the
character '*', causing their values to be obtained from the next
operand, which must be of type int.
- For numeric values, width sets the minimum width of the field and
+ For most values, width is the minimum number of characters to output,
+ padding the formatted form with spaces if necessary.
+ For strings, precision is the maximum number of characters to output,
+ truncating if necessary.
+
+ For floating-point values, width sets the minimum width of the field and
precision sets the number of places after the decimal, if appropriate,
except that for %g/%G it sets the total number of digits. For example,
given 123.45 the format %6.2f prints 123.45 while %.4g prints 123.5.
The default precision for %e and %f is 6; for %g it is the smallest
number of digits necessary to identify the value uniquely.
- For most values, width is the minimum number of characters to output,
- padding the formatted form with spaces if necessary.
- For strings, precision is the maximum number of characters to output,
- truncating if necessary.
+ For complex numbers, the width and precision apply to the two
+ components independently and the result is parenthsized, so %f applied
+ to 1.2+3.4i produces (1.200000+3.400000i).
Other flags:
+ always print a sign for numeric values;