writef.pl -- Old-style formatted write

This library provides writef/1 and friends. These predicates originate from Edinburgh C-Prolog and and provided for compatibility purposes. New code should use format/1, format/2 and friends, which are currently supported by more Prolog implementations.

The writef-family of predicates conflicts with the modern character-esacapes flag about the interpretation of \-sequences. This can be avoided by

Disable character escapes (not recommended unless one wants to run really outdated code unmodified).
Double the \ for conflicting interpretations
Use ISO compliant alternatives for conflicting interpretations

copyright: - Copied from Edinburgh C-Prolog. Original version by Byrd, changed many times since.

writef(+Format) is det

writef(+Format, +Arguments) is det

Formatted write to the current_output. Format is a format specifier. Some escape sequences require arguments that must be provided in the list Arguments. There are two types of escape sequences: special characters start with \ and include arguments start with %. The special character sequences are:

`\n`	Output a newline character
`\l`	Output a line separator (same as `\n`)
`\r`	Output a carriage-return character (ASCII 13)
`\r`	Output a TAB character (ASCII 9)
`\\`	Output `\`
`\%`	Output `%`
`\nnn`	Output character <nnn>. <nnn> is a 1-3 decimal number

Escape sequences to include arguments from Arguments. Each time a %-escape sequence is found in Format the next argument from Arguments is formatted according to the specification.

`%t`	print/1 the next item (mnemonic: term)
`%w`	write/1 the next item
`%q`	writeq/1 the next item
`%d`	display/1 the next item
`%n`	Put the next item as a character
`%r`	Write the next item N times where N is the second item (an integer)
`%s`	Write the next item as a String (so it must be a list of characters)
`%f`	Perform a ttyflush/0 (no items used)
`%Nc`	Write the next item Centered in N columns.
`%Nl`	Write the next item Left justified in N columns.
`%Nr`	Write the next item Right justified in N columns.

deprecated: - New code should use format/1, format/2, etc.

swritef(-String, +Format) is det

swritef(-String, +Format, +Arguments) is det

Use writef/1 or writef/2 and write the result to a string. Note that this is a string in the sense of string_codes/2, not a list of character(-code)s.

deprecated: - . See format/2,3 and/or with_output_to/2.

Re-exported predicates

The following predicates are exported from this file while their implementation is defined in imported modules or non-module files loaded by this module.