From 9eb2967340cf35abebb6bc39be4bcd5fd73f866c Mon Sep 17 00:00:00 2001 From: Přemysl Janouch Date: Sun, 21 May 2017 10:24:14 +0200 Subject: Add arithmetics --- ell.c | 50 +++++++++++++++++++++++++++++++++++++++++++++++++- 1 file changed, 49 insertions(+), 1 deletion(-) diff --git a/ell.c b/ell.c index a148ed1..8905e27 100755 --- a/ell.c +++ b/ell.c @@ -1093,6 +1093,50 @@ defn (fn_system) { return check (ctx, (*result = new_format ("%d", system (command->value)))); } +defn (fn_plus) { + double res = 0.0; + for (; args; args = args->next) { + if (args->type != ITEM_STRING) + return set_error (ctx, "arguments must be strings"); + res += strtod (args->value, NULL); + } + return check (ctx, (*result = new_format ("%f", res))); +} + +defn (fn_minus) { + double res = -0.0; + for (; args; args = args->next) { + if (args->type != ITEM_STRING) + return set_error (ctx, "arguments must be strings"); + res -= strtod (args->value, NULL); + } + return check (ctx, (*result = new_format ("%f", res))); +} + +defn (fn_multiply) { + double res = 1.0; + for (; args; args = args->next) { + if (args->type != ITEM_STRING) + return set_error (ctx, "arguments must be strings"); + res *= strtod (args->value, NULL); + } + return check (ctx, (*result = new_format ("%f", res))); +} + +defn (fn_divide) { + if (!args || args->type != ITEM_STRING) + return set_error (ctx, "first argument must be string"); + double res = strtod (args->value, NULL), x; + for (args = args->next; args; args = args->next) { + if (args->type != ITEM_STRING) + return set_error (ctx, "arguments must be strings"); + if (!(x = strtod (args->value, NULL))) + return set_error (ctx, "division by zero"); + res /= x; + } + return check (ctx, (*result = new_format ("%f", res))); +} + // - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - static bool @@ -1136,7 +1180,11 @@ init_runtime_library (struct context *ctx) { && native_register (ctx, "filter", fn_filter) && native_register (ctx, "print", fn_print) && native_register (ctx, "..", fn_concatenate) - && native_register (ctx, "system", fn_system); + && native_register (ctx, "system", fn_system) + && native_register (ctx, "+", fn_plus) + && native_register (ctx, "-", fn_minus) + && native_register (ctx, "*", fn_multiply) + && native_register (ctx, "/", fn_divide); } // --- Main -------------------------------------------------------------------- -- cgit v1.2.3-70-g09d2