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diff --git a/static/v10/man1/snocone.1 b/static/v10/man1/snocone.1 new file mode 100644 index 00000000..ebe1677f --- /dev/null +++ b/static/v10/man1/snocone.1 @@ -0,0 +1,269 @@ +.TH SNOCONE 1 +.CT 1 prog_other +.SH NAME +snocone \- snobol with syntactic sugar +.SH SYNOPSIS +.B snocone +.I file ... +.SH DESCRIPTION +.I Snocone +is a programming language, syntactically +similar to C, that compiles into +.SM SNOBOL4. +The Snocone compiler translates the concatenation of all +the input files into a +.SM SNOBOL4 +program, which it writes in +.FR a.out . +When +.F a.out +is executed, the +.SM SNOBOL4 +interpreter will automatically be invoked. +A synopsis of Snocone syntax follows. +.SS Lexical conventions +.br +Everything after the first unquoted +.L # +on an input line is ignored. +.br +Statements normally end at the end of the line. +If the last character on a line is an operator, +open parenthesis or bracket, or comma, the statement is +continued on the next line. +.SS "Binary operators, \fRgrouped by decreasing precedence" +.TP +.B [] +Array and table indexing (denoted in +.SM SNOBOL4 +by +.LR <> ). +.PD 0 +.TP +.B $ . +conditional and immediate pattern value assignment, +as in +.SM SNOBOL4 +.TP +.B ^ +power; right-associative as in +.SM SNOBOL4 +.TP +.B * / % +multiplication, division, remainder; +unlike +.SM SNOBOL4, +all have the same precedence. +.TP +.B + - +addition, subtraction +.TP +.B +< > <= >= == != :<: :>: :<=: :>=: :==: :!=: +comparison operators; the ones surrounded by colons +compare strings, the others compare numbers. +These operators behave as +.SM SNOBOL4 +predicates: they return +the null string if the condition is true, +and fail if it is false. +.TP +.B && +concatenation; +evaluates its right operand +only after its left operand has been successfully +evaluated. +It therefore acts as logical +.I and +when applied to predicates. +The null string may be concatenated to any value. +.TP +.B |\^| +the value of the left operand if possible, otherwise +the value of the right operand. +.TP +.B | +pattern value alternation. +.TP +.B ? +pattern match. +Returns the part of the left operand matched by the +right operand, which must be a pattern. +May be used on the left of an assignment +if the left operand is appropriate. +Right-associative. +.TP +.B = +assignment +.PD +.SS Unary operators +.TP +.B + +The numeric equivalent of its argument. +.PD 0 +.TP +.B - +The numeric equivalent of its argument, with the sign reversed. +.TP +.B * +Unevaluated expression, as in +.SM SNOBOL4. +.TP +.B $ +If +.I v +is a value of type +.BR name , +then +.BI $ v +is the variable of that name. +.TP +.B @ +Pattern matching cursor assignment. +.TP +.B ~ +Logical negation: returns the null string if its argument +fails, and fails otherwise. +.TP +.B ? +Returns the null string if its argument succeeds, +and fails otherwise. +.TP +.B \&. +Returns a value of type +.B name +that refers to its (lvalue) argument. +.PD +.SS Statements +.PP +Statements may be prefixed by one or more labels. +A label is an identifier followed by a colon, as in C. +All labels are global: +it is a good idea to prefix labels in procedures +with the name of the procedure. +.TP +.I expression +The given +.I expression +is evaluated for its side effects. +.TP +.BI { " statement ... " } +The +.I statements +are executed sequentially. +.TP +.BI "if (" expression ) " statement \fR[ " else " statement\fR ]" +If evaluation of the +.I expression +succeeds, the first +.I statement +is executed. +Otherwise, the second +.IR statement , +if any, is executed. +An +.I else +belongs to the closest unmatched +.BR if . +.TP +.BI "while (" expression ") " statement +The +.I statement +is executed repeatedly, as long as the +.I expression +can be successfully evaluated. +.TP +.BI "do " statement " while (" expression ) +Like the +.B while +statement, except that the +.I statement +is executed once before the first time the +.I expression +is evaluated. +.TP +.B +for (\fIe1\fP, \fIe2\fP, \fIe3\fP) \fIstatement\fP +As in C, except that commas are used instead of semicolons. +.TP +.BR return " [\fIexpression\fP]" +returns the value of the +.I expression +from the current function. +If +.I expression +fails or is missing, the value returned is that of the +variable with the same name as the function. +If that variable was never set, the function returns +the null string. +.TP +.BR nreturn " [\fIexpression\fP]" +The +.I expression +must be the name of a variable. +That variable is returned from the current +function as an lvalue. +If the +.I expression +fails or is missing, the variable with the +same name as the function must have been set to the +name of a variable. +.TP +.B freturn +The current function returns failure. +.TP +.BI goto " label" +Transfer control to the given +.I label. +.HP Procedures +.PP +Procedures may not be textually nested, but may be recursive +and may call each other in forward references. +The general form of a procedure declaration is: +.IP +.B +procedure \fIname\fP (\fIargs\fP) \fIlocals\fP { \fIstatement ... \fP} +.PP +The +.I args +and +.I locals +are lists of variable names, separated by commas. +Since Snocone is a dynamically typed language, further +declarations are not necessary. +Although procedures are not textually nested, names are +dynamically scoped: a procedure can reference the local variables +and parameters of its caller as if they were global variables. +.HP Input-Output +.PP +Assigning a (string) value to the variable +.L output +causes that value to be written as a single line on the +standard output. +Accessing the variable +.L input +causes a line to be read from the standard input. +The access fails at end of file. +Accessing or assigning to the variable +.L terminal +causes a line to be read from or written to the +standard error file. +Other input-output is as implemented by +the Macrospitbol interpreter; see +.IR langs (1). +.SH SEE ALSO +A. R. Koenig, +`The Snocone Programming Language', +this manual, Volume 2 +.br +.IR langs (1) +.SH BUGS +Run-time diagnostics refer to +.SM SNOBOL4 +source statement numbers, +not to Snocone line numbers. +.br +Extremely long statements can overflow the +.SM SNOBOL4 +compiler's +limits on input line length. |