73 lines
1.4 KiB
Go
73 lines
1.4 KiB
Go
package token;
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import (
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"strings"
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)
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type operation func(Token) Token
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/*
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* LIST: a list of elements
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* OPERAND: a string or number
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* OPERATOR: an entry in a symtable
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* OPERATION: a list starting with an operator
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*/
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type parse_tag int
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const (
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LIST_T parse_tag = iota
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OPERAND_T parse_tag = iota
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OPERATOR_T parse_tag = iota
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OPERATION_T parse_tag = iota
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)
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type Token struct {
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next *Token
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tag parse_tag
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_inner interface{}
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}
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func lex(string input) Token {
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ret := new(Token)
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iter := &ret
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delim := ' '
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var tok strings.Builder
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iter_alloced := false
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for pos, char := range input {
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switch char {
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case '\'', '"', '`':
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delim = char
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case '(':
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delim = ')'
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case delim:
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*iter = new(Token)
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*iter._inner = tok.String()
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iter_alloced = true
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delim = ' '
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default:
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tok.WriteRune(char)
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buf_is_dirty = true
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}
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if iter_alloced {
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iter = &(*iter.next)
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iter_alloced = false
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tok.Reset()
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}
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}
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}
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func parse(Token *arg) {
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// if operand determine if operator
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// determine operator precense in symbol table
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// Determine if a list is an operation or a list
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}
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func eval(Token *tree) *Token {
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// Find operations
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// Simplify operations deepest first
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// return tree of final Tokens
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}
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