You are an expert in writing code in many different languages. Your goal is to perform code completion for the following code, keeping in mind the rest of the code and the file meta data.
    Metadata details:
    filename: solver.go
    path of file: ./repos/gnark/constraint/bn254
    
    the code of the file until where you have to start completion: // Copyright 2020 ConsenSys Software Inc.
//
// Licensed under the Apache License, Version 2.0 (the "License");
// you may not use this file except in compliance with the License.
// You may obtain a copy of the License at
//
//     http://www.apache.org/licenses/LICENSE-2.0
//
// Unless required by applicable law or agreed to in writing, software
// distributed under the License is distributed on an "AS IS" BASIS,
// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either expres
    
func (s *solver) logValue(log constraint.LogEntry) string {
	var toResolve []interface{}
	var (
		eval         fr.Element
		missingValue bool
	)
	for j := 0; j < len(log.ToResolve); j++ {
		// before eval le

		missingValue = false
		eval.SetZero()

		for _, t := range log.ToResolve[j] {
			// for each term in the linear expression

			cID, vID := t.CoeffID(), t.WireID()
			if t.IsConstant() {
				// just add the constant
				eval.Add(&eval, &s.Coefficients[cID])
				continue
			}

			if !s.solved[vID] {
				missingValue = true
				break // stop the loop we can't evaluate.
			}

			tv := s.computeTerm(t)
			eval.Add(&eval, &tv)
		}

		// after
		if missingValue {
			toResolve = append(toResolve, unsolvedVariable)
		} else {
			// we have to append our accumulator
			toResolve = append(toResolve, eval.String())
		}

	}
	if len(log.Stack) > 0 {
		var sbb strings.Builder
		for _, lID := range log.Stack {
			location := s.SymbolTable.Locations[lID]
			function := s.SymbolTable.Functions[location.FunctionID]

			sbb.WriteString(function.Name)
			sbb.WriteByte('\n')
			sbb.WriteByte('\t')
			sbb.WriteString(function.Filename)
			sbb.WriteByte(':')
			sbb.WriteString(strconv.Itoa(int(location.Line)))
			sbb.WriteByte('\n')
		}
		toResolve = append(toResolve, sbb.String())
	}
	return fmt.Sprintf(log.Format, toResolve...)
}