ref: df03eca7e7cbfadf1cf8c8c5a94390eaa5013a8b
dir: /appl/lib/string.b/
implement String; include "string.m"; splitl(s: string, cl: string): (string, string) { n := len s; for(j := 0; j < n; j++) { if(in(s[j], cl)) return (s[0:j], s[j:n]); } return (s,""); } splitr(s: string, cl: string): (string, string) { n := len s; for(j := n-1; j >= 0; j--) { if(in(s[j], cl)) return (s[0:j+1], s[j+1:n]); } return ("",s); } drop(s: string, cl: string): string { n := len s; for(j := 0; j < n; j++) { if(!in(s[j], cl)) return (s[j:n]); } return ""; } take(s: string, cl: string): string { n := len s; for(j := 0; j < n; j++) { if(!in(s[j], cl)) return (s[0:j]); } return s; } in(c: int, s: string): int { n := len s; if(n == 0) return 0; ans := 0; negate := 0; if(s[0] == '^') { negate = 1; s = s[1:]; n--; } for(i := 0; i < n; i++) { if(s[i] == '-' && i > 0 && i < n-1) { if(c >= s[i-1] && c <= s[i+1]) { ans = 1; break; } i++; } else if(c == s[i]) { ans = 1; break; } } if(negate) ans = !ans; return ans; } splitstrl(s: string, t: string): (string, string) { n := len s; nt := len t; if(nt == 0) return ("", s); c0 := t[0]; mainloop: for(j := 0; j <= n-nt; j++) { if(s[j] == c0) { for(k := 1; k < nt; k++) if(s[j+k] != t[k]) continue mainloop; return(s[0:j], s[j:n]); } } return (s,""); } splitstrr(s: string, t: string): (string, string) { n := len s; nt := len t; if(nt == 0) return (s, ""); c0 := t[0]; mainloop: for(j := n-nt; j >= 0; j--) { if(s[j] == c0) { for(k := 1; k < nt; k++) if(s[j+k] != t[k]) continue mainloop; return(s[0:j+nt], s[j+nt:n]); } } return ("",s); } prefix(pre: string, s: string): int { if(len s < len pre) return 0; for(k := 0; k < len pre; k++) if(pre[k] != s[k]) return 0; return 1; } tolower(s: string): string { for(i := 0; i < len s; i++) { c := s[i]; if(c >= 'A' && c <= 'Z') s[i] += 'a' - 'A'; } return s; } toupper(s: string): string { for(i := 0; i < len s; i++) { c := s[i]; if(c >= 'a' && c <= 'z') s[i] += 'A' - 'a'; } return s; } startnum(s: string, base: int): (int, int, int) { if(s == nil || base != 0 && (base < 2 || base > 36)) return (0, 0, 0); # skip possible leading white space c := ' '; for (i := 0; i < len s; i++) { c = s[i]; if(c != ' ' && c != '\t' && c != '\n') break; } # optional sign neg := 0; if(c == '-' || c == '+') { if(c == '-') neg = 1; i++; } if(base == 0) { # parse possible leading base designator start := i; base = -1; for (; i < start+3 && i < len s; i++) { c = s[i]; if (c == 'r' && i > start) { base = int s[start:i]; i++; break; } else if (c < '0' || c > '9') break; } if (base == -1) { i = start; base = 10; } else if (base == 0 || base > 36) return (0, 0, i); } if(i >= len s) return (0, 0, 0); return (base, neg, i); } tobig(s: string, base: int): (big, string) { neg, i: int; (base, neg, i) = startnum(s, base); if(base == 0) return (big 0, s); # parse number itself. # probably this should check for overflow, and max out, as limbo op does? start := i; n := big 0; for (; i < len s; i++) { if((d := digit(s[i], base)) < 0) break; n = n*big base + big d; } if (i == start) return (big 0, s); if (neg) return (-n, s[i:]); return (n, s[i:]); } toint(s: string, base: int): (int, string) { neg, i: int; (base, neg, i) = startnum(s, base); if(base == 0) return (0, s); # parse number itself. # probably this should check for overflow, and max out, as limbo op does? start := i; n := 0; for (; i < len s; i++){ if((d := digit(s[i], base)) < 0) break; n = n*base + d; } if (i == start) return (0, s); if (neg) return (-n, s[i:]); return (n, s[i:]); } digit(c: int, base: int): int { if ('0' <= c && c <= '0' + base - 1) return c-'0'; else if ('a' <= c && c < 'a' + base - 10) return (c - 'a' + 10); else if ('A' <= c && c < 'A' + base - 10) return (c - 'A' + 10); else return -1; } rpow(x: real, n: int): real { inv := 0; if(n < 0){ n = -n; inv = 1; } r := 1.0; for(;;){ if(n&1) r *= x; if((n >>= 1) == 0) break; x *= x; } if(inv) r = 1.0/r; return r; } match(p: string, s: string, i: int): int { if(i+len p > len s) return 0; for(j := 0; j < len p; j++){ c := s[i++]; if(c >= 'A' && c <= 'Z') c += 'a'-'A'; if(p[j] != c) return 0; } return 1; } toreal(s: string, base: int): (real, string) { neg, i: int; (base, neg, i) = startnum(s, base); if(base == 0) return (0.0, s); c := s[i]; if((c == 'i' || c == 'I') && match("infinity", s, i)) return (real s, s[i+8:]); if((c == 'n' || c == 'N') && match("nan", s, i)) return (real s, s[i+3:]); if(digit(c, base) < 0) return (0.0, s); num := 0.0; for(; i < len s && (d := digit(s[i], base)) >= 0; i++) num = num*real base + real d; dig := 0; # digits in fraction if(i < len s && s[i] == '.'){ i++; for(; i < len s && (d = digit(s[i], base)) >= 0; i++){ num = num*real base + real d; dig++; } } exp := 0; eneg := 0; if(i < len s && ((c = s[i]) == 'e' || c == 'E')){ start := i; # might still be badly formed i++; if(i < len s && ((c = s[i]) == '-' || c == '+')){ i++; if(c == '-'){ dig = -dig; eneg = 1; } } if(i < len s && s[i] >= '0' && s[i] <= '9'){ # exponents are always decimal for(; i < len s && (d = digit(s[i], 10)) >= 0; i++) exp = exp*base + d; }else i = start; } if(base == 10) return (real s[0: i], s[i:]); # conversion can be more accurate exp -= dig; if(exp < 0){ exp = -exp; eneg = !eneg; } if(exp < 0 || exp > 19999) exp = 19999; # huge but otherwise arbitrary limit dem := rpow(real base, exp); if(eneg) num /= dem; else num *= dem; if(neg) return (-num,s[i:]); return (num, s[i:]); } append(s: string, l: list of string): list of string { t: list of string; # Reverse l, prepend s, and reverse result. while (l != nil) { t = hd l :: t; l = tl l; } t = s :: t; do { l = hd t :: l; t = tl t; } while (t != nil); return l; } quoted(argv: list of string): string { return quotedc(argv, nil); } quotedc(argv: list of string, cl: string): string { s := ""; while(argv != nil){ arg := hd argv; for(i := 0; i < len arg; i++){ c := arg[i]; if(c == ' ' || c == '\t' || c == '\n' || c == '\'' || in(c, cl)) break; } if(i < len arg || arg == nil){ s += "'" + arg[0:i]; for(; i < len arg; i++){ if (arg[i] == '\'') s[len s] = '\''; s[len s] = arg[i]; } s[len s] = '\''; }else s += arg; if(tl argv != nil) s[len s] = ' '; argv = tl argv; } return s; } unquoted(s: string): list of string { args: list of string; word: string; inquote := 0; for(j := len s; j > 0;){ c := s[j-1]; if(c == ' ' || c == '\t' || c == '\n'){ j--; continue; } for(i := j-1; i >= 0 && ((c = s[i]) != ' ' && c != '\t' && c != '\n' || inquote); i--){ # collect word if(c == '\''){ word = s[i+1:j] + word; j = i; if(!inquote || i == 0 || s[i-1] != '\'') inquote = !inquote; else i--; } } args = (s[i+1:j]+word) :: args; word = nil; j = i; } # if quotes were unbalanced, balance them and try again. if(inquote) return unquoted(s + "'"); return args; }