From cfa37a7b1131abbab2e7d339b451f5f0e3198cc8 Mon Sep 17 00:00:00 2001 From: rsc Date: Sat, 10 Apr 2004 18:53:55 +0000 Subject: Lots of man pages. --- man/man1/hoc.1 | 144 +++++++++++++++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 144 insertions(+) create mode 100644 man/man1/hoc.1 (limited to 'man/man1/hoc.1') diff --git a/man/man1/hoc.1 b/man/man1/hoc.1 new file mode 100644 index 00000000..68a42a6a --- /dev/null +++ b/man/man1/hoc.1 @@ -0,0 +1,144 @@ +.TH HOC 1 +.SH NAME +hoc \- interactive floating point language +.SH SYNOPSIS +.B hoc +[ +.I file ... +] +[ +.B -e +.I expression +] +.SH DESCRIPTION +.I Hoc +interprets a simple language for floating point arithmetic, +at about the level of BASIC, with C-like syntax and +functions. +.PP +The named +.I files +are read and interpreted in order. +If no +.I file +is given or if +.I file +is +.L - +.I hoc +interprets the standard input. +The +.B -e +option allows input to +.I hoc +to be specified on the command line, to be treated as if it appeared in a file. +.PP +.I Hoc +input consists of +.I expressions +and +.IR statements . +Expressions are evaluated and their results printed. +Statements, typically assignments and function or procedure +definitions, produce no output unless they explicitly call +.IR print . +.PP +Variable names have the usual syntax, including +.LR _ ; +the name +.L _ +by itself contains the value of the last expression evaluated. +The variables +.BR E , +.BR PI , +.BR PHI , +.BR GAMMA +and +.B DEG +are predefined; the last is 59.25..., degrees per radian. +.PP +Expressions are formed with these C-like operators, listed by +decreasing precedence. +.TP +.B ^ +exponentiation +.TP +.B ! - ++ -- +.TP +.B * / % +.TP +.B + - +.TP +.B > >= < <= == != +.TP +.B && +.TP +.B || +.TP +.B = += -= *= /= %= +.PP +Built in functions are +.BR abs , +.BR acos , +.BR asin , +.B atan +(one argument), +.BR cos , +.BR cosh , +.BR exp , +.BR int , +.BR log , +.BR log10 , +.BR sin , +.BR sinh , +.BR sqrt , +.BR tan , +and +.BR tanh . +The function +.B read(x) +reads a value into the variable +.B x +and returns 0 at EOF; +the statement +.B print +prints a list of expressions that may include +string constants such as +\fL"hello\en"\f1.\fP +.PP +Control flow statements are +.BR if - else , +.BR while , +and +.BR for , +with braces for grouping. +Newline ends a statement. +Backslash-newline is equivalent to a space. +.PP +Functions and procedures are introduced by the words +.B func +and +.BR proc ; +.B return +is used to return with a value from a function. +.SH EXAMPLES +.EX +func gcd(a, b) { + temp = abs(a) % abs(b) + if(temp == 0) return abs(b) + return gcd(b, temp) +} +for(i=1; i<12; i++) print gcd(i,12) +.EE +.SH SOURCE +.B /sys/src/cmd/hoc +.SH "SEE ALSO" +.IR bc (1), +.IR dc (1) +.br +B. W. Kernighan and R. Pike, +.I +The Unix Programming Environment, +Prentice-Hall, 1984 +.SH BUGS +Error recovery is imperfect within function and procedure definitions. -- cgit v1.2.3