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`format/[2,3]`

`format(`

`+Control`, `+Arguments`)

`format(`

`+Stream`, `+Control`, `+Arguments`)

Interprets the `Arguments` according to the `Control` string and
prints the result on `Stream`.

`Stream`*stream_object*, must be groundDefaults to the current output stream.

`Control`*chars*or*codes*or*atom*, must be groundA string, which can contain control sequences of the form ‘

`~`’:`N``<c>``<c>`a format control option

`N`optional; if given, must be ‘

`*`’ or an integer.

Any characters that are not part of a control sequence are written to the specified output stream.

`:Arguments`*list of term*, must be proper listList of arguments, which will be interpreted and possibly printed by format control options.

If a parameter `N` can be specified, then it can be either an
integer, specified as an optional minus sign followed by a sequence of
decimal digits, or the character ‘`*`’.

If the parameter is specified as ‘`*`’, then the value used will be
the truncated integer value of the next element from `Arguments`
interpreted as a numerical expression.

The following control options cause formatted printing of the next
element from `Arguments` to the current output stream.

- ‘
`~a`’ The argument is an atom. The atom is printed without quoting.

- ‘
`~`’`N`c (Print character.) The argument is a number that will be interpreted as a

*code*.`N`defaults to one and is interpreted as the number of times to print the character. If`N`is zero, or negative, then the character is not printed.- ‘
`~`’`N`e - ‘
`~`’`N`E (Print float in exponential notation.) The argument is a float, which will be printed in exponential notation with one digit before the decimal point and

`N`digits after it. If`N`is zero, or negative, then one digit appears after the decimal point. A sign and at least two digits appear in the exponent, which is introduced by the letter used in the control sequence.`N`defaults to 6.The magnitude of

`N`must be less than 100000, but useful values are much smaller than that.- ‘
`~`’`N`f - ‘
`~`’`N`F (Print float in fixed-point notation.) The argument is a float, which will be printed in fixed-point notation with

`N`digits after the decimal point.`N`may be zero, or negative, in which case a single zero appears after the decimal point. At least one digit appears before the decimal point and at least one after it.`N`defaults to 6.The magnitude of

`N`must be less than 100000, but useful values are much smaller than that.- ‘
`~`’`N`g - ‘
`~`’`N`G (Print float in generic notation.) The argument is a float, which will be printed in ‘

`f`’ or ‘`e`’ (or ‘`E`’ if ‘`G`’ is used) notation with`N`significant digits. If`N`is zero, then one significant digit is printed. ‘`E`’ notation is used if the exponent from its conversion is less than -4 or greater than or equal to`N`, otherwise ‘`f`’ notation. Trailing zeroes are removed from the fractional part of the result. A decimal point and at least one digit after it always appear.`N`defaults to 6.The magnitude of

`N`must be less than 100000, but useful values are much smaller than that.- ‘
`~`’`N`h - ‘
`~`’`N`H (Print float precisely.) The argument is a float, which will be printed in ‘

`f`’ or ‘`e`’ (or ‘`E`’ if ‘`H`’ is used) notation with`d`significant digits, where`d`is the smallest number of digits that will yield the same float when read in. ‘`E`’ notation is used if`N<0`or if the exponent is less than`-N-1`or greater than or equal to`N+d`, otherwise ‘`f`’ notation.`N`defaults to 3.The intuition is that for numbers like 123000000.0, at most

`N`consecutive zeroes before the decimal point are allowed in ‘`f`’ notation. Similarly for numbers like 0.000000123.‘

`E`’ notation is forced by using ‘`~-1H`’. ‘`F`’ is forced by using ‘`~999H`’.The magnitude of

`N`must be less than 100000, but useful values are much smaller than that.- ‘
`~`’`N`d (Print decimal.) The argument is an integer.

`N`is interpreted as the number of digits after the decimal point. If`N`is 0 or missing, then no decimal point will be printed.`N`must be non-negative.- ‘
`~`’`N`D (Print decimal.) The argument is an integer. Identical to ‘

`~`’ except that ‘`N`d`,`’ will separate groups of three digits to the left of the decimal point.- ‘
`~`’`N`r (Print radix.) The argument is an integer.

`N`is interpreted as a radix,*2 \leq N \leq 36*. If`N`is missing, then the radix defaults to 8. The letters ‘`a-z`’ will denote digits larger than 9.- ‘
`~`’`N`R (Print radix.) The argument is an integer. Identical to ‘

`~`’ except that the letters ‘`N`r`A-Z`’ will denote digits larger than 9.- ‘
`~`’`N`s (Print string.) The argument is a code list. If

`N`is zero, or negative, then no characters are output.If

`N`is positive, then the first`N`characters of the code list will be written, and if the code list is exhausted, then extra`SPC`characters will be written, for a total of`N`characters output.- ‘
`~i`’ (Ignore.) The argument, which may be of any type, is ignored.

- ‘
`~k`’ (Print canonical.) The argument may be of any type. The argument will be passed to

`write_canonical/1`

(see ref-iou-tou).- ‘
`~p`’ (Print.) The argument may be of any type. The argument will be passed to

`print/1`

(see ref-iou-tou).- ‘
`~q`’ (Print quoted.) The argument may be of any type. The argument will be passed to

`writeq/1`

(see ref-iou-tou).- ‘
`~w`’ (Write.) The argument may be of any type. The argument will be passed to

`write/1`

(see ref-iou-tou).- ‘
`~@`’ (Call.) The argument

`Arg`is a goal, which will be called as if by`\+ \+`

and is expected to print on the current output stream. If the goal performs other side effects, then the behavior is undefined.`Arg`- ‘
`~~`’ (Print tilde.) Takes no argument. Prints ‘

`~`’.- ‘
`~`’`N`n (Print newline.) Takes no argument. Prints

`N`newlines.`N`defaults to 1.If

`N`is negative or zero, then no newlines are output.- ‘
`~N`’ (Print Newline.) Prints a newline if not at the beginning of a line.

The following control sequences set column boundaries and specify padding. A column is defined as the available space between two consecutive column boundaries on the same line. A boundary is initially assumed at line position 0. The specifications only apply to the line currently being written.

When a column boundary is set (‘`~|`’ or ‘`~+`’) and there are
fewer characters written in the column than its specified width, the
remaining space is divided equally amongst the pad sequences
(‘`~t`’) in the column. If there are no pad sequences, then the column
is space padded at the end.

If ‘`~|`’ or ‘`~+`’ specifies a position preceding the
current position, then the boundary is set at the current position.

- ‘
`~`’`N`| Set a column boundary at line position

`N`.`N`defaults to the current position.The control sequence ‘

`~`’ (with explicit`N`|`N`) will not work correctly on bi-directional streams^{12}, e.g. those created by`library(sockets)`

. A workaround for bi-directional streams may be to use ‘`~|`’ (without explicit`N`) and ‘`~`’, see below.`N`+- ‘
`~`’`N`+ Set a column boundary at

`N`positions past the previous column boundary.`N`defaults to 8.- ‘
`~`’`N`t Specify padding in a column.

`N`is the fill character code.`N`may also be specified as```

where`C``C`is the fill character. The default fill character is`SPC`. Any (‘`~t`’) after the last column boundary on a line is ignored.

Stream errors (see ref-iou-sfh-est), plus:

`consistency_error`

Wrong number of

`Arguments`.`type_error`

`domain_error`

Argument of the wrong type or domain.

| ?-Pi=3.14159265, format('~e ~2E ~0E\n', [Pi,Pi,Pi]).3.141593e+00 3.14E+00 3.0E+00

| ?-Pi=3.14159265, format('~f, ~2F, ~0F\n', [Pi,Pi,Pi]).3.141593, 3.14, 3.0

| ?-format('~g ~2G ~0G\n', [1.23456789e+10, 3.14159265, 0.0123]).1.23457e+10 3.1 0.01

| ?-F = 123000.0, G = 0.000123,format('~h ~h ~2h ~2H ~-1H\n', [F,G,F,G,3.14]).123000.0 0.000123 1.23e+05 1.23E-04 3.14E+00

| ?-format('Hello ~1d world!\n', [42]).Hello 4.2 world! | ?-format('Hello ~d world!\n', [42]).Hello 42 world!

| ?-format('Hello ~1D world!\n', [12345]).Hello 1,234.5 world!

| ?-format('Hello ~2r world!\n', [15]).Hello 1111 world! | ?-format('Hello ~16r world!\n', [15]).Hello f world!

| ?-format('Hello ~16R world!\n', [15]).Hello F world!

| ?-format('Hello ~4s ~4s!\n', ["new","world"]).Hello new worl! | ?-format('Hello ~s world!\n', ["new"]).Hello new world!

| ?-format('Hello ~i~s world!\n', ["old","new"]).Hello new world!

| ?-format('Hello ~k world!\n', [[a,b,c]]).Hello '.'(a,'.'(b,'.'(c,[]))) world!

| ?-assert((portray([X|Y]) :- print(cons(X,Y)))).| ?-format('Hello ~p world!\n', [[a,b,c]]).Hello cons(a,cons(b,cons(c,[]))) world!

| ?-format('Hello ~q world!\n', [['A','B']]).Hello ['A','B'] world!

| ?-format('Hello ~w world!\n', [['A','B']]).Hello [A,B] world!

| ?-format('Hello ~@ world!\n', [write(new)]).Hello new world!

| ?-format('Hello ~~ world!\n', []).Hello ~ world!

| ?-format('Hello ~n world!\n', []).Hello world!

| ?-format('~`*t NICE TABLE ~`*t~61|~n', []),format('*~t*~61|~n', []),format('*~t~a~20|~t~a~t~20+~a~t~20+~t*~61|~n',['Right aligned','Centered','Left aligned']),format('*~t~d~20|~t~d~t~20+~d~t~20+~t*~61|~n',[123,45,678]),format('*~t~d~20|~t~d~t~20+~d~t~20+~t*~61|~n',[1,2345,6789]),format('~`*t~61|~n', []).

************************ NICE TABLE ************************* * * * Right aligned Centered Left aligned * * 123 45 678 * * 1 2345 6789 * *************************************************************

| ?-format('Table of Contents ~t ~a~72|~*n', [i,3]),format('~tTable of Contents~t~72|~*n', 2),format("1. Documentation supplement for ~s~1f ~`.t ~d~72|~*n", ["Quintus Prolog Release ",1.5,2,2]),format("~t~*+~w Definition of the term \"loaded\" ~`.t ~d~72|~n", [3,1-1,2]),format("~t~*+~w Finding all solutions ~`.t ~d~72|~n", [3,1-2,3]),format("~t~*+~w Searching for a file in a library ~`.t ~d~72|~n", [3,1-3,4]),format("~t~*+~w New Built-in Predicates ~`.t ~d~72|~n", [3,1-4,5]),format("~t~*+~w write_canonical (?Term) ~`.t ~d~72|~n", [7,1-4-1,5]),format("~*+.~n~*+.~n~*+.~n", [20,20,20]),format("~t~*+~w File Specifications ~`.t ~d~72|~n", [3,1-7,17]),format("~t~*+~w multifile(+PredSpec) ~`.t ~d~72|~n", [7,1-7-1,18]).

Table of Contents 1. Documentation supplement for Quintus Prolog Release 1.5 ........... 2 1-1 Definition of the term "loaded" ............................... 2 1-2 Finding all solutions ......................................... 3 1-3 Searching for a file in a library ............................. 4 1-4 New Built-in Predicates ....................................... 5 1-4-1 write_canonical (?Term) ................................. 5 . . . 1-7 File Specifications .......................................... 17 1-7-1 multifile(+PredSpec) ................................... 18

This is because streams only have one counter for line position, and for bidirectional streams that counter tracks the input direction (see cpg-ref-SP_get_stream_counts).

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