summaryrefslogtreecommitdiff
path: root/src/cmd/yacc/units.y
diff options
context:
space:
mode:
Diffstat (limited to 'src/cmd/yacc/units.y')
-rw-r--r--src/cmd/yacc/units.y768
1 files changed, 0 insertions, 768 deletions
diff --git a/src/cmd/yacc/units.y b/src/cmd/yacc/units.y
deleted file mode 100644
index 9c1b0b336..000000000
--- a/src/cmd/yacc/units.y
+++ /dev/null
@@ -1,768 +0,0 @@
-// Derived from Plan 9's /sys/src/cmd/units.y
-// http://plan9.bell-labs.com/sources/plan9/sys/src/cmd/units.y
-//
-// Copyright (C) 2003, Lucent Technologies Inc. and others. All Rights Reserved.
-// Portions Copyright 2009 The Go Authors. All Rights Reserved.
-// Distributed under the terms of the Lucent Public License Version 1.02
-// See http://plan9.bell-labs.com/plan9/license.html
-
-// Generate parser with prefix "units_":
-// go tool yacc -p "units_"
-
-%{
-
-// This tag will end up in the generated y.go, so that forgetting
-// 'make clean' does not fail the next build.
-
-// +build ignore
-
-// units.y
-// example of a Go yacc program
-// usage is
-// go tool yacc -p "units_" units.y (produces y.go)
-// go build -o units y.go
-// ./units $GOROOT/src/cmd/yacc/units.txt
-// you have: c
-// you want: furlongs/fortnight
-// * 1.8026178e+12
-// / 5.5474878e-13
-// you have:
-
-package main
-
-import (
- "bufio"
- "flag"
- "fmt"
- "math"
- "runtime"
- "os"
- "path/filepath"
- "strconv"
- "unicode/utf8"
-)
-
-const (
- Ndim = 15 // number of dimensions
- Maxe = 695 // log of largest number
-)
-
-type Node struct {
- vval float64
- dim [Ndim]int8
-}
-
-type Var struct {
- name string
- node Node
-}
-
-var fi *bufio.Reader // input
-var fund [Ndim]*Var // names of fundamental units
-var line string // current input line
-var lineno int // current input line number
-var linep int // index to next rune in unput
-var nerrors int // error count
-var one Node // constant one
-var peekrune rune // backup runt from input
-var retnode1 Node
-var retnode2 Node
-var retnode Node
-var sym string
-var vflag bool
-%}
-
-%union {
- node Node
- vvar *Var
- numb int
- vval float64
-}
-
-%type <node> prog expr expr0 expr1 expr2 expr3 expr4
-
-%token <vval> VÄL // dieresis to test UTF-8
-%token <vvar> VAR
-%token <numb> _SUP // tests leading underscore in token name
-%%
-prog:
- ':' VAR expr
- {
- var f int
- f = int($2.node.dim[0])
- $2.node = $3
- $2.node.dim[0] = 1
- if f != 0 {
- Errorf("redefinition of %v", $2.name)
- } else if vflag {
- fmt.Printf("%v\t%v\n", $2.name, &$2.node)
- }
- }
-| ':' VAR '#'
- {
- var f, i int
- for i = 1; i < Ndim; i++ {
- if fund[i] == nil {
- break
- }
- }
- if i >= Ndim {
- Error("too many dimensions")
- i = Ndim - 1
- }
- fund[i] = $2
- f = int($2.node.dim[0])
- $2.node = one
- $2.node.dim[0] = 1
- $2.node.dim[i] = 1
- if f != 0 {
- Errorf("redefinition of %v", $2.name)
- } else if vflag {
- fmt.Printf("%v\t#\n", $2.name)
- }
- }
-| ':'
- {
- }
-| '?' expr
- {
- retnode1 = $2
- }
-| '?'
- {
- retnode1 = one
- }
-
-expr:
- expr4
-| expr '+' expr4
- {
- add(&$$, &$1, &$3)
- }
-| expr '-' expr4
- {
- sub(&$$, &$1, &$3)
- }
-
-expr4:
- expr3
-| expr4 '*' expr3
- {
- mul(&$$, &$1, &$3)
- }
-| expr4 '/' expr3
- {
- div(&$$, &$1, &$3)
- }
-
-expr3:
- expr2
-| expr3 expr2
- {
- mul(&$$, &$1, &$2)
- }
-
-expr2:
- expr1
-| expr2 _SUP
- {
- xpn(&$$, &$1, $2)
- }
-| expr2 '^' expr1
- {
- var i int
- for i = 1; i < Ndim; i++ {
- if $3.dim[i] != 0 {
- Error("exponent has units")
- $$ = $1
- break
- }
- }
- if i >= Ndim {
- i = int($3.vval)
- if float64(i) != $3.vval {
- Error("exponent not integral")
- }
- xpn(&$$, &$1, i)
- }
- }
-
-expr1:
- expr0
-| expr1 '|' expr0
- {
- div(&$$, &$1, &$3)
- }
-
-expr0:
- VAR
- {
- if $1.node.dim[0] == 0 {
- Errorf("undefined %v", $1.name)
- $$ = one
- } else {
- $$ = $1.node
- }
- }
-| VÄL
- {
- $$ = one
- $$.vval = $1
- }
-| '(' expr ')'
- {
- $$ = $2
- }
-%%
-
-type UnitsLex int
-
-func (UnitsLex) Lex(yylval *units_SymType) int {
- var c rune
- var i int
-
- c = peekrune
- peekrune = ' '
-
-loop:
- if (c >= '0' && c <= '9') || c == '.' {
- goto numb
- }
- if ralpha(c) {
- goto alpha
- }
- switch c {
- case ' ', '\t':
- c = getrune()
- goto loop
- case '×':
- return '*'
- case '÷':
- return '/'
- case '¹', 'ⁱ':
- yylval.numb = 1
- return _SUP
- case '²', '⁲':
- yylval.numb = 2
- return _SUP
- case '³', '⁳':
- yylval.numb = 3
- return _SUP
- }
- return int(c)
-
-alpha:
- sym = ""
- for i = 0; ; i++ {
- sym += string(c)
- c = getrune()
- if !ralpha(c) {
- break
- }
- }
- peekrune = c
- yylval.vvar = lookup(0)
- return VAR
-
-numb:
- sym = ""
- for i = 0; ; i++ {
- sym += string(c)
- c = getrune()
- if !rdigit(c) {
- break
- }
- }
- peekrune = c
- f, err := strconv.ParseFloat(sym, 64)
- if err != nil {
- fmt.Printf("error converting %v\n", sym)
- f = 0
- }
- yylval.vval = f
- return VÄL
-}
-
-func (UnitsLex) Error(s string) {
- Errorf("syntax error, last name: %v", sym)
-}
-
-func main() {
- var file string
-
- flag.BoolVar(&vflag, "v", false, "verbose")
-
- flag.Parse()
-
- file = filepath.Join(runtime.GOROOT(), "src/cmd/yacc/units.txt")
- if flag.NArg() > 0 {
- file = flag.Arg(0)
- } else if file == "" {
- fmt.Fprintf(os.Stderr, "cannot find data file units.txt; provide it as argument or set $GOROOT\n")
- os.Exit(1)
- }
-
- f, err := os.Open(file)
- if err != nil {
- fmt.Fprintf(os.Stderr, "error opening %v: %v\n", file, err)
- os.Exit(1)
- }
- fi = bufio.NewReader(f)
-
- one.vval = 1
-
- /*
- * read the 'units' file to
- * develop a database
- */
- lineno = 0
- for {
- lineno++
- if readline() {
- break
- }
- if len(line) == 0 || line[0] == '/' {
- continue
- }
- peekrune = ':'
- units_Parse(UnitsLex(0))
- }
-
- /*
- * read the console to
- * print ratio of pairs
- */
- fi = bufio.NewReader(os.NewFile(0, "stdin"))
-
- lineno = 0
- for {
- if (lineno & 1) != 0 {
- fmt.Printf("you want: ")
- } else {
- fmt.Printf("you have: ")
- }
- if readline() {
- break
- }
- peekrune = '?'
- nerrors = 0
- units_Parse(UnitsLex(0))
- if nerrors != 0 {
- continue
- }
- if (lineno & 1) != 0 {
- if specialcase(&retnode, &retnode2, &retnode1) {
- fmt.Printf("\tis %v\n", &retnode)
- } else {
- div(&retnode, &retnode2, &retnode1)
- fmt.Printf("\t* %v\n", &retnode)
- div(&retnode, &retnode1, &retnode2)
- fmt.Printf("\t/ %v\n", &retnode)
- }
- } else {
- retnode2 = retnode1
- }
- lineno++
- }
- fmt.Printf("\n")
- os.Exit(0)
-}
-
-/*
- * all characters that have some
- * meaning. rest are usable as names
- */
-func ralpha(c rune) bool {
- switch c {
- case 0, '+', '-', '*', '/', '[', ']', '(', ')',
- '^', ':', '?', ' ', '\t', '.', '|', '#',
- '×', '÷', '¹', 'ⁱ', '²', '⁲', '³', '⁳':
- return false
- }
- return true
-}
-
-/*
- * number forming character
- */
-func rdigit(c rune) bool {
- switch c {
- case '0', '1', '2', '3', '4', '5', '6', '7', '8', '9',
- '.', 'e', '+', '-':
- return true
- }
- return false
-}
-
-func Errorf(s string, v ...interface{}) {
- fmt.Printf("%v: %v\n\t", lineno, line)
- fmt.Printf(s, v...)
- fmt.Printf("\n")
-
- nerrors++
- if nerrors > 5 {
- fmt.Printf("too many errors\n")
- os.Exit(1)
- }
-}
-
-func Error(s string) {
- Errorf("%s", s)
-}
-
-func add(c, a, b *Node) {
- var i int
- var d int8
-
- for i = 0; i < Ndim; i++ {
- d = a.dim[i]
- c.dim[i] = d
- if d != b.dim[i] {
- Error("add must be like units")
- }
- }
- c.vval = fadd(a.vval, b.vval)
-}
-
-func sub(c, a, b *Node) {
- var i int
- var d int8
-
- for i = 0; i < Ndim; i++ {
- d = a.dim[i]
- c.dim[i] = d
- if d != b.dim[i] {
- Error("sub must be like units")
- }
- }
- c.vval = fadd(a.vval, -b.vval)
-}
-
-func mul(c, a, b *Node) {
- var i int
-
- for i = 0; i < Ndim; i++ {
- c.dim[i] = a.dim[i] + b.dim[i]
- }
- c.vval = fmul(a.vval, b.vval)
-}
-
-func div(c, a, b *Node) {
- var i int
-
- for i = 0; i < Ndim; i++ {
- c.dim[i] = a.dim[i] - b.dim[i]
- }
- c.vval = fdiv(a.vval, b.vval)
-}
-
-func xpn(c, a *Node, b int) {
- var i int
-
- *c = one
- if b < 0 {
- b = -b
- for i = 0; i < b; i++ {
- div(c, c, a)
- }
- } else {
- for i = 0; i < b; i++ {
- mul(c, c, a)
- }
- }
-}
-
-func specialcase(c, a, b *Node) bool {
- var i int
- var d, d1, d2 int8
-
- d1 = 0
- d2 = 0
- for i = 1; i < Ndim; i++ {
- d = a.dim[i]
- if d != 0 {
- if d != 1 || d1 != 0 {
- return false
- }
- d1 = int8(i)
- }
- d = b.dim[i]
- if d != 0 {
- if d != 1 || d2 != 0 {
- return false
- }
- d2 = int8(i)
- }
- }
- if d1 == 0 || d2 == 0 {
- return false
- }
-
- if fund[d1].name == "°C" && fund[d2].name == "°F" &&
- b.vval == 1 {
- for ll := 0; ll < len(c.dim); ll++ {
- c.dim[ll] = b.dim[ll]
- }
- c.vval = a.vval*9./5. + 32.
- return true
- }
-
- if fund[d1].name == "°F" && fund[d2].name == "°C" &&
- b.vval == 1 {
- for ll := 0; ll < len(c.dim); ll++ {
- c.dim[ll] = b.dim[ll]
- }
- c.vval = (a.vval - 32.) * 5. / 9.
- return true
- }
- return false
-}
-
-func printdim(str string, d, n int) string {
- var v *Var
-
- if n != 0 {
- v = fund[d]
- if v != nil {
- str += fmt.Sprintf("%v", v.name)
- } else {
- str += fmt.Sprintf("[%d]", d)
- }
- switch n {
- case 1:
- break
- case 2:
- str += "²"
- case 3:
- str += "³"
- default:
- str += fmt.Sprintf("^%d", n)
- }
- }
- return str
-}
-
-func (n Node) String() string {
- var str string
- var f, i, d int
-
- str = fmt.Sprintf("%.7e ", n.vval)
-
- f = 0
- for i = 1; i < Ndim; i++ {
- d = int(n.dim[i])
- if d > 0 {
- str = printdim(str, i, d)
- } else if d < 0 {
- f = 1
- }
- }
-
- if f != 0 {
- str += " /"
- for i = 1; i < Ndim; i++ {
- d = int(n.dim[i])
- if d < 0 {
- str = printdim(str, i, -d)
- }
- }
- }
-
- return str
-}
-
-func (v *Var) String() string {
- var str string
- str = fmt.Sprintf("%v %v", v.name, v.node)
- return str
-}
-
-func readline() bool {
- s, err := fi.ReadString('\n')
- if err != nil {
- return true
- }
- line = s
- linep = 0
- return false
-}
-
-func getrune() rune {
- var c rune
- var n int
-
- if linep >= len(line) {
- return 0
- }
- c, n = utf8.DecodeRuneInString(line[linep:len(line)])
- linep += n
- if c == '\n' {
- c = 0
- }
- return c
-}
-
-var symmap = make(map[string]*Var) // symbol table
-
-func lookup(f int) *Var {
- var p float64
- var w *Var
-
- v, ok := symmap[sym]
- if ok {
- return v
- }
- if f != 0 {
- return nil
- }
- v = new(Var)
- v.name = sym
- symmap[sym] = v
-
- p = 1
- for {
- p = fmul(p, pname())
- if p == 0 {
- break
- }
- w = lookup(1)
- if w != nil {
- v.node = w.node
- v.node.vval = fmul(v.node.vval, p)
- break
- }
- }
- return v
-}
-
-type Prefix struct {
- vval float64
- name string
-}
-
-var prefix = []Prefix{ // prefix table
- {1e-24, "yocto"},
- {1e-21, "zepto"},
- {1e-18, "atto"},
- {1e-15, "femto"},
- {1e-12, "pico"},
- {1e-9, "nano"},
- {1e-6, "micro"},
- {1e-6, "μ"},
- {1e-3, "milli"},
- {1e-2, "centi"},
- {1e-1, "deci"},
- {1e1, "deka"},
- {1e2, "hecta"},
- {1e2, "hecto"},
- {1e3, "kilo"},
- {1e6, "mega"},
- {1e6, "meg"},
- {1e9, "giga"},
- {1e12, "tera"},
- {1e15, "peta"},
- {1e18, "exa"},
- {1e21, "zetta"},
- {1e24, "yotta"},
-}
-
-func pname() float64 {
- var i, j, n int
- var s string
-
- /*
- * rip off normal prefixs
- */
- n = len(sym)
- for i = 0; i < len(prefix); i++ {
- s = prefix[i].name
- j = len(s)
- if j < n && sym[0:j] == s {
- sym = sym[j:n]
- return prefix[i].vval
- }
- }
-
- /*
- * rip off 's' suffixes
- */
- if n > 2 && sym[n-1] == 's' {
- sym = sym[0 : n-1]
- return 1
- }
-
- return 0
-}
-
-// careful multiplication
-// exponents (log) are checked before multiply
-func fmul(a, b float64) float64 {
- var l float64
-
- if b <= 0 {
- if b == 0 {
- return 0
- }
- l = math.Log(-b)
- } else {
- l = math.Log(b)
- }
-
- if a <= 0 {
- if a == 0 {
- return 0
- }
- l += math.Log(-a)
- } else {
- l += math.Log(a)
- }
-
- if l > Maxe {
- Error("overflow in multiply")
- return 1
- }
- if l < -Maxe {
- Error("underflow in multiply")
- return 0
- }
- return a * b
-}
-
-// careful division
-// exponents (log) are checked before divide
-func fdiv(a, b float64) float64 {
- var l float64
-
- if b <= 0 {
- if b == 0 {
- Errorf("division by zero: %v %v", a, b)
- return 1
- }
- l = math.Log(-b)
- } else {
- l = math.Log(b)
- }
-
- if a <= 0 {
- if a == 0 {
- return 0
- }
- l -= math.Log(-a)
- } else {
- l -= math.Log(a)
- }
-
- if l < -Maxe {
- Error("overflow in divide")
- return 1
- }
- if l > Maxe {
- Error("underflow in divide")
- return 0
- }
- return a / b
-}
-
-func fadd(a, b float64) float64 {
- return a + b
-}
generated by cgit v1.2.3 (git 2.39.1) at 2024-06-10 01:41:08 +0000