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comparison man/lispref/strings.texi @ 280:7df0dd720c89 r21-0b38

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Import from CVS: tag r21-0b38
author cvs
date Mon, 13 Aug 2007 10:32:22 +0200
parents fe104dbd9147
children 558f606b08ae
comparison
equal deleted inserted replaced
279:c20b2fb5bb0a 280:7df0dd720c89
112 @end defun 112 @end defun
113 113
114 @defun char-or-string-p object 114 @defun char-or-string-p object
115 This function returns @code{t} if @var{object} is a string or a 115 This function returns @code{t} if @var{object} is a string or a
116 character, @code{nil} otherwise. 116 character, @code{nil} otherwise.
117
118 In XEmacs addition, this function also returns @code{t} if @var{object}
119 is an integer that can be represented as a character. This is because
120 of compatibility with previous XEmacs and should not be depended on.
117 @end defun 121 @end defun
118 122
119 @node Creating Strings 123 @node Creating Strings
120 @section Creating Strings 124 @section Creating Strings
121 125
122 The following functions create strings, either from scratch, or by 126 The following functions create strings, either from scratch, or by
123 putting strings together, or by taking them apart. 127 putting strings together, or by taking them apart.
128
129 @defun string &rest characters
130 This function returns of string made up of @var{characters}.
131
132 @example
133 (string ?X ?E ?m ?a ?c ?s)
134 @result{} "XEmacs"
135 (string)
136 @result{} ""
137 @end example
138
139 Analogous functions operating on other data types include @code{list},
140 @code{cons} (@pxref{Building Lists}), @code{vector} (@pxref{Vectors})
141 and @code{bit-vector} (@pxref{Bit Vectors}). This function has not been
142 available in XEmacs prior to 21.0 and FSF Emacs prior to 20.3.
143 @end defun
124 144
125 @defun make-string count character 145 @defun make-string count character
126 This function returns a string made up of @var{count} repetitions of 146 This function returns a string made up of @var{count} repetitions of
127 @var{character}. If @var{count} is negative, an error is signaled. 147 @var{character}. If @var{count} is negative, an error is signaled.
128 148
536 @code{int-to-string} is a semi-obsolete alias for this function. 556 @code{int-to-string} is a semi-obsolete alias for this function.
537 557
538 See also the function @code{format} in @ref{Formatting Strings}. 558 See also the function @code{format} in @ref{Formatting Strings}.
539 @end defun 559 @end defun
540 560
541 @defun string-to-number string 561 @defun string-to-number string &optional base
542 @cindex string to number 562 @cindex string to number
543 This function returns the numeric value of the characters in 563 This function returns the numeric value of the characters in
544 @var{string}, read in base ten. It skips spaces and tabs at the 564 @var{string}, read in @var{base}. It skips spaces and tabs at the
545 beginning of @var{string}, then reads as much of @var{string} as it can 565 beginning of @var{string}, then reads as much of @var{string} as it can
546 interpret as a number. (On some systems it ignores other whitespace at 566 interpret as a number. (On some systems it ignores other whitespace at
547 the beginning, not just spaces and tabs.) If the first character after 567 the beginning, not just spaces and tabs.) If the first character after
548 the ignored whitespace is not a digit or a minus sign, this function 568 the ignored whitespace is not a digit or a minus sign, this function
549 returns 0. 569 returns 0.
570
571 If @var{base} is not specified, it defaults to ten. With @var{base}
572 other than ten, only integers can be read.
550 573
551 @example 574 @example
552 (string-to-number "256") 575 (string-to-number "256")
553 @result{} 256 576 @result{} 256
554 (string-to-number "25 is a perfect square.") 577 (string-to-number "25 is a perfect square.")
555 @result{} 25 578 @result{} 25
556 (string-to-number "X256") 579 (string-to-number "X256")
557 @result{} 0 580 @result{} 0
558 (string-to-number "-4.5") 581 (string-to-number "-4.5")
559 @result{} -4.5 582 @result{} -4.5
583 (string-to-number "ffff" 16)
584 @result{} 65535
560 @end example 585 @end example
561 586
562 @findex string-to-int 587 @findex string-to-int
563 @code{string-to-int} is an obsolete alias for this function. 588 @code{string-to-int} is an obsolete alias for this function.
564 @end defun 589 @end defun
736 integer followed by a @samp{$}. 761 integer followed by a @samp{$}.
737 762
738 @item 763 @item
739 Zero or more of the optional flag characters @samp{-}, @samp{+}, 764 Zero or more of the optional flag characters @samp{-}, @samp{+},
740 @samp{ }, @samp{0}, and @samp{#}. 765 @samp{ }, @samp{0}, and @samp{#}.
766
767 @item
768 An asterisk (@samp{*}, meaning that the field width is now assumed to
769 have been specified as an argument.
741 770
742 @item 771 @item
743 An optional minimum field width. 772 An optional minimum field width.
744 773
745 @item 774 @item