From 23aee50b1c406071e04ce710bec431f116fb6f11 Mon Sep 17 00:00:00 2001
From: bugwheels94 <bugwheels94@gmail.com>
Date: Mon, 18 Nov 2024 03:53:44 +0000
Subject: [PATCH] fix: fix issue 61

fix #91
---
 dist/browser/math-expression-evaluator.min.js |  2 +-
 src/lexer.ts                                  |  2 +-
 test/issue91.js                               | 12 ++++++++++++
 3 files changed, 14 insertions(+), 2 deletions(-)
 create mode 100644 test/issue91.js

diff --git a/dist/browser/math-expression-evaluator.min.js b/dist/browser/math-expression-evaluator.min.js
index 7efea94..c275e91 100644
--- a/dist/browser/math-expression-evaluator.min.js
+++ b/dist/browser/math-expression-evaluator.min.js
@@ -1 +1 @@
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o={0:!0,1:!0,3:!0,4:!0,6:!0,8:!0,9:!0,12:!0,13:!0,14:!0},h={0:!0,1:!0,2:!0,3:!0,4:!0,5:!0,6:!0,7:!0,8:!0,9:!0,10:!0,11:!0,12:!0,13:!0},r={0:!0,3:!0,4:!0,8:!0,12:!0,13:!0},u={},s={0:!0,1:!0,3:!0,4:!0,6:!0,8:!0,12:!0,13:!0},p={1:!0},i=[[],["1","2","3","7","8","9","4","5","6","+","-","*","/","(",")","^","!","P","C","e","0",".",",","n"," ","&"],["pi","ln","Pi"],["sin","cos","tan","Del","int","Mod","log","pow"],["asin","acos","atan","cosh","root","tanh","sinh"],["acosh","atanh","asinh","Sigma"]];function l(e,t,n,a){for(var o=0;o<a;o++)if(e[n+o]!==t[o])return!1;return!0}function E(e){for(var a=0;a<e.length;a++){var o=e[a].token.length,h=-1;e[a].type===t.FUNCTION_WITH_N_ARGS&&void 0===e[a].numberOfArguments&&(e[a].numberOfArguments=2),i[o]=i[o]||[];for(var r=0;r<i[o].length;r++)if(e[a].token===i[o][r]){h=N(i[o][r],this.tokens);break}-1===h?(this.tokens.push(e[a]),e[a].precedence=n[e[a].type],i.length<=e[a].token.length&&(i[e[a].token.length]=[]),i[e[a].token.length].push(e[a].token)):(this.tokens[h]=e[a],e[a].precedence=n[e[a].type])}}function N(e,t){for(var n=0;n<t.length;n++)if(t[n].token===e)return n;return-1}var v=function(e,n){var E,v={value:this.math.changeSign,type:t.FUNCTION_WITH_ONE_ARG,precedence:4,show:"-"},f={value:")",show:")",type:t.CLOSING_PARENTHESIS,precedence:0},y={value:"(",type:t.OPENING_PARENTHESIS,precedence:0,show:"("},A=[y],c=[],_=e,O=o,T=0,R=u,I="";void 0!==n&&this.addToken(n);var w=function(e,t){for(var n,a,o,h=[],r=t.length,u=0;u<r;u++)if(!(u<r-1&&" "===t[u]&&" "===t[u+1])){for(n="",a=t.length-u>i.length-2?i.length-1:t.length-u;a>0;a--)if(void 0!==i[a])for(o=0;o<i[a].length;o++)l(t,i[a][o],u,a)&&(n=i[a][o],o=i[a].length,a=0);if(u+=n.length-1,""===n)throw new Error("Can't understand after "+t.slice(u));h.push(e.tokens[N(n,e.tokens)])}return h}(this,_);for(E=0;E<w.length;E++){var P=w[E];if(14!==P.type){var m,M=P.token,g=P.type,C=P.value,d=P.precedence,k=P.show,S=A[A.length-1];for(m=c.length;m--&&0===c[m];)if(-1!==[t.FUNCTION_WITH_ONE_ARG,t.BINARY_OPERATOR_HIGH_PRECENDENCE,t.CONSTANT,t.OPENING_PARENTHESIS,t.CLOSING_PARENTHESIS,t.BINARY_OPERATOR_LOW_PRECENDENCE,t.BINARY_OPERATOR_PERMUTATION,t.COMMA,t.EVALUATED_FUNCTION,t.EVALUATED_FUNCTION_PARAMETER].indexOf(g)){if(!0!==O[g])throw new Error(M+" is not allowed after "+I);A.push(f),O=h,R=s,c.pop()}if(!0!==O[g])throw new Error(M+" is not allowed after "+I);!0===R[g]&&(g=t.BINARY_OPERATOR_HIGH_PRECENDENCE,C=this.math.mul,k="&times;",d=3,E-=1);var U={value:C,type:g,precedence:d,show:k,numberOfArguments:P.numberOfArguments};if(g===t.FUNCTION_WITH_ONE_ARG)O=o,R=u,a(c,1),A.push(U),w[E+1].type!==t.OPENING_PARENTHESIS&&(A.push(y),c.push(2));else if(g===t.NUMBER)S.type===t.NUMBER?(S.value+=C,a(c,1)):A.push(U),O=h,R=r;else if(g===t.BINARY_OPERATOR_HIGH_PRECENDENCE)O=o,R=u,a(c,2),A.push(U);else if(g===t.CONSTANT)A.push(U),O=h,R=s;else if(g===t.OPENING_PARENTHESIS)a(c,1),T++,O=o,R=u,A.push(U);else if(g===t.CLOSING_PARENTHESIS){if(!T)throw new Error("Closing parenthesis are more than opening one, wait What!!!");T--,O=h,R=s,A.push(U),a(c,1)}else if(g===t.DECIMAL){if(S.hasDec)throw new Error("Two decimals are not allowed in one number");S.type!==t.NUMBER&&(S={show:"0",value:0,type:t.NUMBER,precedence:0},A.push(S)),O=p,a(c,1),R=u,S.value+=C,S.hasDec=!0}else g===t.POSTFIX_FUNCTION_WITH_ONE_ARG&&(O=h,R=s,a(c,1),A.push(U));g===t.FUNCTION_WITH_N_ARGS?(O=o,R=u,a(c,P.numberOfArguments+2),A.push(U),w[E+1].type!==t.OPENING_PARENTHESIS&&(A.push(y),c.push(P.numberOfArguments+2))):g===t.BINARY_OPERATOR_LOW_PRECENDENCE?(S.type===t.BINARY_OPERATOR_LOW_PRECENDENCE?S.value===this.math.add?(S.value=C,S.show=k,a(c,1)):S.value===this.math.sub&&"-"===k&&(S.value=this.math.add,S.show="+",a(c,1)):S.type!==t.CLOSING_PARENTHESIS&&S.type!==t.POSTFIX_FUNCTION_WITH_ONE_ARG&&S.type!==t.NUMBER&&S.type!==t.CONSTANT&&S.type!==t.EVALUATED_FUNCTION_PARAMETER?"-"===M&&(O=o,R=u,a(c,1).push(2),A.push(v),A.push(y)):(A.push(U),a(c,2)),O=o,R=u):g===t.BINARY_OPERATOR_PERMUTATION?(O=o,R=u,a(c,2),A.push(U)):g===t.COMMA?(O=o,R=u,A.push(U)):g===t.EVALUATED_FUNCTION?(O=o,R=u,a(c,6),A.push(U),w[E+1].type!==t.OPENING_PARENTHESIS&&(A.push(y),c.push(6))):g===t.EVALUATED_FUNCTION_PARAMETER&&(O=h,R=s,A.push(U)),a(c,-1),I=M}else if(E>0&&E<w.length-1&&1===w[E+1].type&&(1===w[E-1].type||6===w[E-1].type))throw new Error("Unexpected Space")}for(m=c.length;m--;)A.push(f);if(!0!==O[5])throw new Error("complete the expression");for(;T--;)A.push(f);return A.push(f),A};function f(e){for(var t,n,a,o=[],h=-1,r=-1,u=[{value:"(",type:4,precedence:0,show:"("}],s=1;s<e.length;s++)if(1===e[s].type||3===e[s].type||13===e[s].type)1===e[s].type&&(e[s].value=Number(e[s].value)),o.push(e[s]);else if(4===e[s].type)u.push(e[s]);else if(5===e[s].type)for(;4!==(null==(p=n=u.pop())?void 0:p.type);){var p;n&&o.push(n)}else if(11===e[s].type){for(;4!==(null==(i=n=u.pop())?void 0:i.type);){var i;n&&o.push(n)}u.push(n)}else{r=(t=e[s]).precedence,h=(a=u[u.length-1]).precedence;var l="Math.pow"==a.value&&"Math.pow"==t.value;if(r>h)u.push(t);else{for(;h>=r&&!l||l&&r<h;)n=u.pop(),a=u[u.length-1],n&&o.push(n),h=a.precedence,l="Math.pow"==t.value&&"Math.pow"==a.value;u.push(t)}}return o}function y(e,t){(t=t||{}).PI=Math.PI,t.E=Math.E;for(var n,a,o,h=[],r=void 0!==t.n,u=0;u<e.length;u++)if(1===e[u].type)h.push({value:e[u].value,type:1});else if(3===e[u].type)h.push({value:t[e[u].value],type:1});else if(0===e[u].type){var s=h[h.length-1];Array.isArray(s)?s.push(e[u]):s.value=e[u].value(s.value)}else if(7===e[u].type){var p=h[h.length-1];Array.isArray(p)?p.push(e[u]):p.value=e[u].value(p.value)}else if(8===e[u].type){for(var i=[],l=0;l<e[u].numberOfArguments;l++){var E=h.pop();E&&i.push(E.value)}h.push({type:1,value:e[u].value.apply(e[u],i.reverse())})}else if(10===e[u].type)n=h.pop(),a=h.pop(),Array.isArray(a)?((a=a.concat(n)).push(e[u]),h.push(a)):Array.isArray(n)?(n.unshift(a),n.push(e[u]),h.push(n)):h.push({type:1,value:e[u].value(a.value,n.value)});else if(2===e[u].type||9===e[u].type)n=h.pop(),a=h.pop(),Array.isArray(a)?((a=a.concat(n)).push(e[u]),h.push(a)):Array.isArray(n)?(n.unshift(a),n.push(e[u]),h.push(n)):h.push({type:1,value:e[u].value(a.value,n.value)});else if(12===e[u].type){n=h.pop();var N=void 0;N=!Array.isArray(n)&&n?[n]:n||[],a=h.pop(),o=h.pop(),h.push({type:1,value:e[u].value(o.value,a.value,N)})}else 13===e[u].type&&(r?h.push({value:t[e[u].value],type:3}):h.push([e[u]]));if(h.length>1)throw new Error("Uncaught Syntax error");return parseFloat(h[0].value.toFixed(15))}var A=function(){function t(){var t;this.toPostfix=f,this.addToken=E,this.lex=v,this.postfixEval=y,this.math=(t=this,{isDegree:!0,acos:function(e){return t.math.isDegree?180/Math.PI*Math.acos(e):Math.acos(e)},add:function(e,t){return e+t},asin:function(e){return t.math.isDegree?180/Math.PI*Math.asin(e):Math.asin(e)},atan:function(e){return t.math.isDegree?180/Math.PI*Math.atan(e):Math.atan(e)},acosh:function(e){return Math.log(e+Math.sqrt(e*e-1))},asinh:function(e){return Math.log(e+Math.sqrt(e*e+1))},atanh:function(e){return Math.log((1+e)/(1-e))},C:function(e,n){var a=1,o=e-n,h=n;h<o&&(h=o,o=n);for(var r=h+1;r<=e;r++)a*=r;var u=t.math.fact(o);return"NaN"===u?"NaN":a/u},changeSign:function(e){return-e},cos:function(e){return t.math.isDegree&&(e=t.math.toRadian(e)),Math.cos(e)},cosh:function(e){return(Math.pow(Math.E,e)+Math.pow(Math.E,-1*e))/2},div:function(e,t){return e/t},fact:function(e){if(e%1!=0)return"NaN";for(var t=1,n=2;n<=e;n++)t*=n;return t},inverse:function(e){return 1/e},log:function(e){return Math.log(e)/Math.log(10)},mod:function(e,t){return e%t},mul:function(e,t){return e*t},P:function(e,t){for(var n=1,a=Math.floor(e)-Math.floor(t)+1;a<=Math.floor(e);a++)n*=a;return n},Pi:function(e,n,a){for(var o=1,h=e;h<=n;h++)o*=Number(t.postfixEval(a,{n:h}));return o},pow10x:function(e){for(var t=1;e--;)t*=10;return t},sigma:function(e,n,a){for(var o=0,h=e;h<=n;h++)o+=Number(t.postfixEval(a,{n:h}));return o},sin:function(e){return t.math.isDegree&&(e=t.math.toRadian(e)),Math.sin(e)},sinh:function(e){return(Math.pow(Math.E,e)-Math.pow(Math.E,-1*e))/2},sub:function(e,t){return e-t},tan:function(e){return t.math.isDegree&&(e=t.math.toRadian(e)),Math.tan(e)},tanh:function(e){return t.math.sinh(e)/t.math.cosh(e)},toRadian:function(e){return e*Math.PI/180},and:function(e,t){return e&t}}),this.tokens=function(t){return[{token:"sin",show:"sin",type:0,value:t.math.sin},{token:"cos",show:"cos",type:0,value:t.math.cos},{token:"tan",show:"tan",type:0,value:t.math.tan},{token:"pi",show:"&pi;",type:3,value:"PI"},{token:"(",show:"(",type:4,value:"("},{token:")",show:")",type:5,value:")"},{token:"P",show:"P",type:10,value:t.math.P},{token:"C",show:"C",type:10,value:t.math.C},{token:" ",show:" ",type:14,value:" ".anchor},{token:"asin",show:"asin",type:0,value:t.math.asin},{token:"acos",show:"acos",type:0,value:t.math.acos},{token:"atan",show:"atan",type:0,value:t.math.atan},{token:"7",show:"7",type:1,value:"7"},{token:"8",show:"8",type:1,value:"8"},{token:"9",show:"9",type:1,value:"9"},{token:"int",show:"Int",type:0,value:Math.floor},{token:"cosh",show:"cosh",type:0,value:t.math.cosh},{token:"acosh",show:"acosh",type:0,value:t.math.acosh},{token:"ln",show:" ln",type:0,value:Math.log},{token:"^",show:"^",type:10,value:Math.pow},{token:"root",show:"root",type:0,value:Math.sqrt},{token:"4",show:"4",type:1,value:"4"},{token:"5",show:"5",type:1,value:"5"},{token:"6",show:"6",type:1,value:"6"},{token:"/",show:"&divide;",type:2,value:t.math.div},{token:"!",show:"!",type:7,value:t.math.fact},{token:"tanh",show:"tanh",type:0,value:t.math.tanh},{token:"atanh",show:"atanh",type:0,value:t.math.atanh},{token:"Mod",show:" Mod ",type:2,value:t.math.mod},{token:"1",show:"1",type:1,value:"1"},{token:"2",show:"2",type:1,value:"2"},{token:"3",show:"3",type:1,value:"3"},{token:"*",show:"&times;",type:2,value:t.math.mul},{token:"sinh",show:"sinh",type:0,value:t.math.sinh},{token:"asinh",show:"asinh",type:0,value:t.math.asinh},{token:"e",show:"e",type:3,value:"E"},{token:"log",show:" log",type:0,value:t.math.log},{token:"0",show:"0",type:1,value:"0"},{token:".",show:".",type:6,value:"."},{token:"+",show:"+",type:9,value:t.math.add},{token:"-",show:"-",type:9,value:t.math.sub},{token:",",show:",",type:11,value:","},{token:"Sigma",show:"&Sigma;",type:12,value:t.math.sigma},{token:"n",show:"n",type:13,value:"n"},{token:"Pi",show:"&Pi;",type:12,value:t.math.Pi},{token:"pow",show:"pow",type:8,value:Math.pow,numberOfArguments:2},{token:"&",show:"&",type:9,value:t.math.and}].map((function(t){return e({},t,{precedence:n[t.type]})}))}(this)}return t.prototype.eval=function(e,t,n){return this.postfixEval(this.toPostfix(this.lex(e,t)),n)},t}();return A.TOKEN_TYPES=t,A.tokenTypes=t,A}));
diff --git a/src/lexer.ts b/src/lexer.ts
index 521759e..db5abfe 100644
--- a/src/lexer.ts
+++ b/src/lexer.ts
@@ -296,7 +296,7 @@ export const lex = function (this: Mexp, inp: string, tokens?: Token[]) {
     if (cType === tokenTypes.FUNCTION_WITH_ONE_ARG) {
       allowed = type0;
       asterick = empty;
-      inc(ptc, 2);
+      inc(ptc, 1);
       str.push(obj);
       if (nodes[i + 1].type !== tokenTypes.OPENING_PARENTHESIS) {
         str.push(openingParObj);
diff --git a/test/issue91.js b/test/issue91.js
new file mode 100644
index 0000000..bb53a6e
--- /dev/null
+++ b/test/issue91.js
@@ -0,0 +1,12 @@
+// This test is for node JS
+
+var assert = require('assert')
+var Mexp = require('../dist/es/index.js')
+var mexp = new Mexp()
+describe('Testing Issue #91', function () {
+	it('should work subtracting functions', function () {
+		assert.equal(
+			mexp.eval('sincos1-sincos1'),
+			0
+		)
+	})})