1 cfa37a7b 2004-04-10 devnull .TH HOC 1
  2 cfa37a7b 2004-04-10 devnull .SH NAME
  3 cfa37a7b 2004-04-10 devnull hoc \- interactive floating point language
  4 cfa37a7b 2004-04-10 devnull .SH SYNOPSIS
  5 cfa37a7b 2004-04-10 devnull .B hoc
  6 cfa37a7b 2004-04-10 devnull [
  7 cfa37a7b 2004-04-10 devnull .I file ...
  8 cfa37a7b 2004-04-10 devnull ]
  9 cfa37a7b 2004-04-10 devnull [
 10 cfa37a7b 2004-04-10 devnull .B -e
 11 cfa37a7b 2004-04-10 devnull .I expression
 12 cfa37a7b 2004-04-10 devnull ]
 13 cfa37a7b 2004-04-10 devnull .SH DESCRIPTION
 14 cfa37a7b 2004-04-10 devnull .I Hoc
 15 cfa37a7b 2004-04-10 devnull interprets a simple language for floating point arithmetic,
 16 cfa37a7b 2004-04-10 devnull at about the level of BASIC, with C-like syntax and
 17 cfa37a7b 2004-04-10 devnull functions.
 18 cfa37a7b 2004-04-10 devnull .PP
 19 cfa37a7b 2004-04-10 devnull The named
 20 cfa37a7b 2004-04-10 devnull .I files
 21 cfa37a7b 2004-04-10 devnull are read and interpreted in order.
 22 cfa37a7b 2004-04-10 devnull If no
 23 cfa37a7b 2004-04-10 devnull .I file
 24 cfa37a7b 2004-04-10 devnull is given or if
 25 cfa37a7b 2004-04-10 devnull .I file
 26 cfa37a7b 2004-04-10 devnull is
 27 cfa37a7b 2004-04-10 devnull .L -
 28 cfa37a7b 2004-04-10 devnull .I hoc
 29 cfa37a7b 2004-04-10 devnull interprets the standard input.
 30 cfa37a7b 2004-04-10 devnull The
 31 cfa37a7b 2004-04-10 devnull .B -e
 32 cfa37a7b 2004-04-10 devnull option allows input to
 33 cfa37a7b 2004-04-10 devnull .I hoc
 34 cfa37a7b 2004-04-10 devnull to be specified on the command line, to be treated as if it appeared in a file.
 35 cfa37a7b 2004-04-10 devnull .PP
 36 cfa37a7b 2004-04-10 devnull .I Hoc
 37 cfa37a7b 2004-04-10 devnull input consists of
 38 cfa37a7b 2004-04-10 devnull .I expressions
 39 cfa37a7b 2004-04-10 devnull and
 40 cfa37a7b 2004-04-10 devnull .IR statements .
 41 cfa37a7b 2004-04-10 devnull Expressions are evaluated and their results printed.
 42 cfa37a7b 2004-04-10 devnull Statements, typically assignments and function or procedure
 43 cfa37a7b 2004-04-10 devnull definitions, produce no output unless they explicitly call
 44 cfa37a7b 2004-04-10 devnull .IR print .
 45 cfa37a7b 2004-04-10 devnull .PP
 46 cfa37a7b 2004-04-10 devnull Variable names have the usual syntax, including 
 47 cfa37a7b 2004-04-10 devnull .LR _ ;
 48 cfa37a7b 2004-04-10 devnull the name 
 49 cfa37a7b 2004-04-10 devnull .L _
 50 cfa37a7b 2004-04-10 devnull by itself contains the value of the last expression evaluated.
 51 cfa37a7b 2004-04-10 devnull The variables
 52 cfa37a7b 2004-04-10 devnull .BR E ,
 53 cfa37a7b 2004-04-10 devnull .BR PI ,
 54 cfa37a7b 2004-04-10 devnull .BR PHI ,
 55 cfa37a7b 2004-04-10 devnull .BR GAMMA
 56 cfa37a7b 2004-04-10 devnull and
 57 cfa37a7b 2004-04-10 devnull .B DEG 
 58 cfa37a7b 2004-04-10 devnull are predefined; the last is 59.25..., degrees per radian.
 59 cfa37a7b 2004-04-10 devnull .PP
 60 cfa37a7b 2004-04-10 devnull Expressions are formed with these C-like operators, listed by
 61 cfa37a7b 2004-04-10 devnull decreasing precedence.
 62 cfa37a7b 2004-04-10 devnull .TP
 63 cfa37a7b 2004-04-10 devnull .B ^
 64 cfa37a7b 2004-04-10 devnull exponentiation
 65 cfa37a7b 2004-04-10 devnull .TP
 66 cfa37a7b 2004-04-10 devnull .B ! - ++ --
 67 cfa37a7b 2004-04-10 devnull .TP
 68 cfa37a7b 2004-04-10 devnull .B * / %
 69 cfa37a7b 2004-04-10 devnull .TP
 70 cfa37a7b 2004-04-10 devnull .B + -
 71 cfa37a7b 2004-04-10 devnull .TP
 72 cfa37a7b 2004-04-10 devnull .B > >= < <= == !=
 73 cfa37a7b 2004-04-10 devnull .TP
 74 cfa37a7b 2004-04-10 devnull .B &&
 75 cfa37a7b 2004-04-10 devnull .TP
 76 cfa37a7b 2004-04-10 devnull .B ||
 77 cfa37a7b 2004-04-10 devnull .TP
 78 cfa37a7b 2004-04-10 devnull .B = += -= *= /= %=
 79 cfa37a7b 2004-04-10 devnull .PP
 80 cfa37a7b 2004-04-10 devnull Built in functions are
 81 cfa37a7b 2004-04-10 devnull .BR abs ,
 82 cfa37a7b 2004-04-10 devnull .BR acos ,
 83 cfa37a7b 2004-04-10 devnull .BR asin ,
 84 cfa37a7b 2004-04-10 devnull .B atan
 85 cfa37a7b 2004-04-10 devnull (one argument),
 86 cfa37a7b 2004-04-10 devnull .BR cos ,
 87 cfa37a7b 2004-04-10 devnull .BR cosh ,
 88 cfa37a7b 2004-04-10 devnull .BR exp ,
 89 cfa37a7b 2004-04-10 devnull .BR int ,
 90 cfa37a7b 2004-04-10 devnull .BR log ,
 91 cfa37a7b 2004-04-10 devnull .BR log10 ,
 92 cfa37a7b 2004-04-10 devnull .BR sin ,
 93 cfa37a7b 2004-04-10 devnull .BR sinh ,
 94 cfa37a7b 2004-04-10 devnull .BR sqrt ,
 95 cfa37a7b 2004-04-10 devnull .BR tan ,
 96 cfa37a7b 2004-04-10 devnull and
 97 cfa37a7b 2004-04-10 devnull .BR tanh .
 98 cfa37a7b 2004-04-10 devnull The function
 99 cfa37a7b 2004-04-10 devnull .B read(x)
100 cfa37a7b 2004-04-10 devnull reads a value into the variable
101 cfa37a7b 2004-04-10 devnull .B x
102 cfa37a7b 2004-04-10 devnull and returns 0 at EOF;
103 cfa37a7b 2004-04-10 devnull the statement
104 cfa37a7b 2004-04-10 devnull .B print
105 cfa37a7b 2004-04-10 devnull prints a list of expressions that may include
106 cfa37a7b 2004-04-10 devnull string constants such as
107 cfa37a7b 2004-04-10 devnull \fL"hello\en"\f1.\fP
108 cfa37a7b 2004-04-10 devnull .PP
109 cfa37a7b 2004-04-10 devnull Control flow statements are
110 cfa37a7b 2004-04-10 devnull .BR if - else ,
111 cfa37a7b 2004-04-10 devnull .BR while ,
112 cfa37a7b 2004-04-10 devnull and
113 cfa37a7b 2004-04-10 devnull .BR for ,
114 cfa37a7b 2004-04-10 devnull with braces for grouping.
115 cfa37a7b 2004-04-10 devnull Newline ends a statement.
116 cfa37a7b 2004-04-10 devnull Backslash-newline is equivalent to a space.
117 cfa37a7b 2004-04-10 devnull .PP
118 cfa37a7b 2004-04-10 devnull Functions and procedures are introduced by the words
119 cfa37a7b 2004-04-10 devnull .B func
120 cfa37a7b 2004-04-10 devnull and
121 cfa37a7b 2004-04-10 devnull .BR proc ;
122 cfa37a7b 2004-04-10 devnull .B return
123 cfa37a7b 2004-04-10 devnull is used to return with a value from a function.
124 cfa37a7b 2004-04-10 devnull .SH EXAMPLES
125 cfa37a7b 2004-04-10 devnull .EX
126 cfa37a7b 2004-04-10 devnull func gcd(a, b) {
127 cfa37a7b 2004-04-10 devnull 	temp = abs(a) % abs(b)
128 cfa37a7b 2004-04-10 devnull 	if(temp == 0) return abs(b)
129 cfa37a7b 2004-04-10 devnull 	return gcd(b, temp)
130 cfa37a7b 2004-04-10 devnull }
131 cfa37a7b 2004-04-10 devnull for(i=1; i<12; i++) print gcd(i,12)
132 cfa37a7b 2004-04-10 devnull .EE
133 cfa37a7b 2004-04-10 devnull .SH SOURCE
134 c3674de4 2005-01-11 devnull .B \*9/src/cmd/hoc
135 cfa37a7b 2004-04-10 devnull .SH "SEE ALSO"
136 d32deab1 2020-08-16 rsc .MR bc (1) ,
137 d32deab1 2020-08-16 rsc .MR dc (1)
138 cfa37a7b 2004-04-10 devnull .br
139 cfa37a7b 2004-04-10 devnull B. W. Kernighan and R. Pike,
140 cfa37a7b 2004-04-10 devnull .I
141 cfa37a7b 2004-04-10 devnull The Unix Programming Environment,
142 cfa37a7b 2004-04-10 devnull Prentice-Hall, 1984
143 cfa37a7b 2004-04-10 devnull .SH BUGS
144 cfa37a7b 2004-04-10 devnull Error recovery is imperfect within function and procedure definitions.